Newspaper Articles

Great Hostabilities

By Dawn Pettinelli, UConn Home & Garden Education Center

Hostas in a garden
Image by dmp2024

So versatile and ubiquitous are hostas that I have yet to visit a garden that doesn’t have at least one whether left by a previous gardener or selected by the present one. Hostas certainly are workhorses of the garden renowned for their shade tolerance, hardiness and longevity. Plus, few plants have such large variations in size, leaf color and texture. According to the American Hosta Society, there are more than 3000 varieties of hostas covering 45 species including stalwarts of our gardens such as Hosta sieboldiana, H. elegans and H. montana. Now the hostas you purchase are likely complex crosses of multiple species.

Hostas are native to Asia and came to the United States through Europe during the 1800s. Many of us older gardeners referred to them as plantain lilies because their broad leaves resemble a common weed (or herb depending on one’s perspective), plantain. The young leaves are reputedly edible. In fact, the Japanese are said to serve them raw, boiled or fried in tempura. Their palatability probably explains why gardeners around here half-jokingly refer to them as ‘deer candy’.

Hostas are divided by size into 5 groups. Minis are less than 6 inches tall, small range from 7 to 10 inches, medium from 11 to 18, large from 19 to 28, and giants are greater than 28 inches. ‘Gentle Giant’ and ‘Empress Wu’ are close to 4 feet tall with a spread of over 5 feet, if you’re looking for a plant to make a voluminous impression. Keep in mind a plant’s full size when incorporating them into your planting beds.

A notable feature of many hosta cultivars is leaf variegation. On marginally variegated plants the edges of the leaves are light in color, maybe cream or yellow. Medio variegated types have light colored centers with darker edges. There are also 5 groupings for color: green, blue and gold, plus the 2 types of variegation. The gold and variegated cultivars do best in part sun to dappled shade. Placed in a heavily shaded area, they can lose some of their color as only the green parts of the leaves photosynthesize.

Hosta leaves up close with raindrops
Image by dmp2024

Leaf shapes range from thin and smooth to ridged and heart shaped. Sizes range from 2 inches on ‘Mouse Ears’ to over a foot and a half on giant hostas.

While grown mainly for their attractive foliage, hostas do bloom once a year. Most have delicate-looking, tubular flowers in various shades of purple that are attractive to hummingbirds and bees. Fragrant white ‘Royal Standard’ grace part of a patio in my white garden. Their heady scent is especially pronounced on warm summer evenings. ‘Royal Wedding’ is another fragrant, white-flowering variety. Cut down the flower stalks once flowering is finished.

Growing hostas is a breeze. These tough, dependable plants put on their best show when not located in full sun as the large leaves can scorch during periods of hot, sunny weather. That being said, there are some cultivars like ‘Guacamole’ and ‘Paradigm’ which can tolerate full sun with adequate moisture.

An ideal location would be a semi- to fully shaded site in a soil with a pH in the mid 6s and moderate fertility. Hostas are often planted under trees as once established they can tolerate dry shade to some extent. Remember that a tree’s roots will be competing with the hostas and your plants would benefit from extra water and fertilizer.

The two major pests of hostas are slugs and deer. Ragged holes and tears on leaves are a sign of slugs. These soft-bodied creatures feed at night or on cloudy days but slime trails on the leaves or ground may be visible in the morning. Controls include hand-picking, beer traps, diatomaceous earth and slug baits.

Deer can make short work of a bed of hostas. Three strategies are to use repellents, fence them out or plant your hostas amid less appetizing plants. Some have reported less deer damage to blue leaved hostas, maybe because they have a waxy coating. If you’re growing hostas in deer country, you’ll have to figure out what works best for you.

At the end of the season, frost will flatten the leaves of your hostas. Cut them back and remove the foliage from your garden to give both slugs and diseases less places to overwinter. Plants typically need division every few years if they are outgrowing their allotted spaces. Dig up and divide in the spring when the new stems start to poke through the soil but before the leaves unfurl.

If you have questions about growing hostas or any other gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu

Calling the Cut – Tree Triage, Care, and Removal

By Nick Goltz, DPM, UConn Plant Diagnostic Lab/UConn Home & Garden Education Center

The forecast is looking good for a perfect 4th of July weekend. Most folks will take advantage of the weather ahead to plan that perfect grilling menu for when their friends and family visit. This is a much-needed respite from the severe weather that passed through over the past few weeks. Severe winds and torrential rains hammered Connecticut and most of the rest of the Northeast after a recent heat wave. With the weather for the week ahead of us is looking much better than the weather of the week behind us, now is the perfect time to assess our trees and determine if any action needs to be taken before the next storm comes!

Tree with branches missing on one side.
Storm damage caused this tree to lose branches on one side. This lopsidedness increases risk to property below. Photo by H. Zidack

I’ll start and end this column with the advice that a professional arborist should be called-in if you are ever unsure of your tree’s health, or if you need support regarding safe management and potential removal. In Connecticut, one of the best resources for finding a licensed, local arborist as well as additional resources regarding tree care and maintenance can be found on the Connecticut Tree Protective Association website, ctpa.org. That said, tree triage can start with you at home. There are many things one can be on the lookout for to determine if a tree need professional attention, and potentially in what order the work should be done.

I’m sure you’ve heard this phrase used to describe real estate, but with trees too, location is everything. The first thing to consider when performing your tree triage is the location of the tree. Regardless of tree age, size, species, or health, the trees that should always merit our immediate attention are those in locations where they could pose a danger to life or property if a limb were to fall off or if the tree were to topple altogether. Trees within striking distance of homes, power lines, and important structures like chicken coops and pet houses should always be the first inspected before the storm comes and after it passes. If a tree knocks down a power line or hits a home, call for help. Never attempt to work around a live cable (one that still carries electricity) without the proper training and equipment.

The second thing to consider as you perform your tree triage is health of the tree. Trees weakened by disease or age are more likely to succumb to strong winds or topple after standing water weakens or kills roots. Inspect your trees for symptoms of stress and disease such as branches that no longer produce leaves. Depending on the species of tree, a few may not be much cause for concern, but if there are several branches on a tree that no longer produce new leaves or needles, the tree is likely not in great health. Another symptom of stress or disease is a visible canker, or large wound, on the trunk of the tree. Trees in good health will typically grow new tissue over an injury sustained by pruning, animal feeding, or a previous storm. Cankers that appear to be getting larger over a few years, rather than smaller, are often a cause for concern.

There are even some obvious signs of disease such as conk or shelf mushrooms that grow directly from the wood of the tree. While these organisms are important for nutrient cycling in natural ecosystems, they often indicate that a tree is approaching the end of its life. The shelf mushroom is only the sexual structure of the fungus, there to produce spores and reach new trees. While removing the mushroom may slow the spread of the fungus to other trees nearby, the majority of the “body” of the fungus will still exist within the tree, weakening it by breaking down woody tissue over time.

Trees, like other living things, do not live indefinitely and become more vulnerable to illness and stress as they age. Just like people need to take care of themselves to ensure they live a long, healthy life, so too must trees be cared for over the course of their lives to ensure they have the best possible outcome. Regular fertilization and pruning are essential to not only ensure that a tree grows robustly, but also that it does not become lopsided or heavy on one side as it ages. Even healthy trees can fall if they are never pruned and have a poor center of gravity! Pruning should be performed frequently to promote new growth, discourage lopsidedness, and allow increased airflow through the canopy. This will have the double benefit of decreasing disease pressure that often accompanies high canopy humidity and prolonged leaf wetness. Though it depends on the species of tree, most here in New England perform best when pruned while they are dormant in winter. Remember to not remove more than 1/3 of the tree’s branches when pruning, if possible!

There are other factors to consider when determining if a tree should come down that we don’t have space to discuss at length here, such as the species of tree, whether the tree is used for other purposes (such as part of a living fence), whether the tree has historic or personal significance, or what removal of the tree may mean for other plants nearby that depend on its shade. And, of course, nobody should consider tree removal without considering cost and time. If cost is a concern, remember to do your triage and prioritize the management of trees that could potentially damage your home, property, or power lines if they were to fall. These considerations and others are worth discussing with an arborist as they survey your property!

For questions about planting and pruning trees or other gardening topics, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu or contact your local Cooperative Extension Center.

Remove Those Suckers!

By Dawn Pettinelli, UConn Home & Garden Education Center

About now the gardens should be planted, and it is time to turn our attention to the trees and shrubs on the property. New growth is almost fully expanded and pruning of spring flowering shrubs can commence. When out there with your pruners, keep an eye peeled for suckers and water sprouts, both on the plants you’re pruning and other woody plants in the yard.

A pear tree with multiple suckers growing from the base. Photo by dmp2024

Many trees and shrubs produce vigorous, upright stems that can reach several feet high over the growing season if left unchecked. Those arising from the root system are known as suckers while those growths arising from the crown portion of a tree or large shrub are referred to as water sprouts. At the very least, they are unattractive and take away from the architectural framework of a plant. More importantly they use water, nutrients and energy that could be put to better use if not taken from the rest of the plant. If not removed, they can crowd out the main plant resulting in reduced vigor.

Some woody plants naturally tend to produce suckers and sometimes these young vigorous shoots are needed to rejuvenate older plants as aging stems are removed. An example would be shrubs like red-twigged dogwoods or lilacs. Suckers arising from trees such as apples, crabapples, honey locust, lindens and others, however, should be removed.

In the case of grafted plants, like hybrid tea roses or apples, the desired variety is grafted on to a rootstock that might be more cold hardy, have dwarfing genes or other desired features. Occasionally the rootstock revolts, so to speak, and sends up its own shoots. In the case of roses, one might notice a stem with red flowers when the plant was purchased as a named cultivar with different colored flowers.

Suckers and water sprouts often occur because plants are in some way stressed or due to damage to their root system. Plants can be under stress for a number of reasons. Some common reasons would be insect or disease problems, drought, too high of a water table, compacted soil and/or difficult growing conditions.

Planting too deep will also stress a plant and could cause suckers to develop. Whenever planting woody plants sink them so that the level of soil in the pot they are grown in is level with the soil they are planted in.

Another reason for suckers or water sprouts is that plants are pruned incorrectly or too drastically. Seldom is it advisable to remove more than one-third of the plant at one time. Also, avoid topping ornamental or woodland trees.

Ideally suckers and water sprouts should be removed as soon as they are produced. Often, they can just be rubbed or twisted off in spring as their stem is just starting to expand. Once they reach pencil-size in thickness, cut with clean, sharp pruners. Do your best to remove them flush to a limb or as close to the tree’s trunk or root system as you can. Don’t leave stubs as these will likely have buds at their base and just regrow.

Speaking of suckers, there are often questions when growing tomatoes about what to do with the sprouts popping up where the leaf attaches to the main stem. Typically suckers just form on indeterminate tomato varieties, which are those that continue to grow, bloom and set fruit as long as growing conditions allow.  If all suckers are left on the plant, it becomes quite unruly and hard to stake. Also, fruit will be plentiful but usually smaller.

Usually, the suckers below the first fruiting cluster are removed so the development of those tomatoes won’t be slowed. Then it is up to individual gardeners to decide whether to leave suckers or not and how many to leave. Often a few are left to increase and extend the harvest. Tomatoes in our area are prone to many leaf diseases, especially during humid and wet seasons. As the bottom leaves yellow and die, it is beneficial to let some of the suckers on top grow so plants can produce more foliage to yield food for the plant and to shade the developing fruit. Some experimentation might be necessary keeping in mind that it is better to remove too little than too much.

For questions about pruning suckers and water sprouts or on other gardening topics, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu or contact your local Cooperative Extension Center.

Firefly Petunias Light Up the Night

By Dr. Matthew Lisy, UConn Adjunct Faculty

A pot of white flowered firefly petunias
Firefly Petunias by Day. (Photo by M. Lissy)

The world of genetics has really had a tremendous impact on our lives. There is a lot of talk about GMOs, or genetically modified organisms, in the news. Labels even alert us to the presence of these crops in our foods. I wanted to share a new plant called the Firefly Petunia. It was not fireflies, but mushrooms that gave this plant its ability to glow. This is known as bioluminescence in the world of biology.

Through feats of genetic engineering, a gene is taken from one organism and placed into another.  This is where people become worried. Humans, however, have been doing this for hundreds of years. The best looking or most productive organisms were bred together for the next generation.  This is called selective breeding, and it essentially concentrates beneficial versions of genes in the offspring.

Now what is determined to be the most beautiful is truly in the eye of the beholder. Some people, for example, selected for white flowers in a normally purple flowered species, Echinacea purpurea. Some have even taken things a step farther and crossed different species of plants to obtain new colors of flowers. In nature, separate species have evolved isolation mechanisms to maintain their identity. When our plant breeders force a cross of the species boundary, much of the time it was done with closely related species of plants within the same genus.  A great example of this is the crossing of Echinacea purpurea, the purple cone flower, with Echinacea paradoxa, the yellow cone flower. This was done to obtain hybrid offspring that have red or orange flowers. These were back crossed with the parent varieties, so they have the same growth habit and form, but with new colored flowers.

Firefly petunia flowers glowing green in the dark.
Firefly petunias by night. This is no trick, the plants actually glow (photo by M. Lisy)

This hybridizing never really ruffled many feathers though, as the plants were very closely related anyway. More modern GMOs, like our Firefly Petunias, are obtained not through “natural” pollination processes, but through genetic manipulation. Scientists literally take one or more genes from one species and place them in another. These species are not closely related, so it may become an ethical conundrum. Here, one may ask if we should take a gene from a mushroom and place it into a plant. A similar circumstance was seen over twenty years ago in the aquarium industry, where genes from corals and jellyfish were placed into tropical fish to make them fluorescent Glofish.

On the question of ethics, I cannot tell you what to think, or what is right or wrong. We each will need to answer that question for ourselves. It does remind me of a quote from Jurassic Park, where Dr. Ian Malcolm states “…your scientists were so preoccupied with whether or not they could that they didn’t stop to think if they should.” The real question is where do we go from here. For the fish, it was species after species of Glofish, and for me, the novelty started wearing off. After all, how many species will be made fluorescent before it just gets boring? Now for our plants, will we have roads lined with glowing trees to eliminate the need for streetlights? Will we have glowing houseplants that function like night lights? Ultimately, it will be up to you, the consumer.

For me, this is just cool science. We ship and plant petunias all over the world. Are these glowing petunias going to cause any harm? Probably not, as none of the other ones have. When I go outside at night to take the dog out and see the bioluminescent petunias, it puts a smile on my face. It reminds me of the fact that we, as humans, are capable of many things. I can’t help but ponder if this will inspire a sense of awe and wonderment in our children. Maybe some may even study genetics because of these petunias. What if one of them ends up finding a cure for a debilitating human disease, all because of a glowing plant? And while some may say that this daydream of mine is just science fiction, need I remind you that so were glowing plants a few years ago?

For your gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.ladybug.uconn.edu or contact your local Cooperative Extension center.

 

Seen any Sawflies?

By Dawn Pettinelli, UConn Home & Garden Education Center

Hibiscus sawfly larvae on hibiscus leaf. Photo by dmp2024

Gardeners know that amidst the promises of each new growing season come its challenges, usually in the form of weather or pests. A common insect pest this time of year are sawfly larvae, which feed on some of our favorite plants including roses, azaleas, perennial hibiscus, dogwoods, and some pines. If populations are high, significant damage can occur.

Sawfly adults are small, short-lived insects slightly resembling wasps to which they are related but their waists are generally thicker. Their ovipositor (egg-laying appendage) is somewhat saw-like in appearance, hence their common name. Eggs may be laid singly or in groups.

Larvae look like small caterpillars but there is a distinctive difference between caterpillars in the Lepidoptera family that transform into butterflies and moths, and sawfly larvae in the Hymenoptera family. Larvae in both families have numerous pairs of legs. From the head, the first three pairs are thoracic legs that correspond to an adult insects’ three pairs of legs. Count the number of fleshy leg pairs (pro-legs) after that. Caterpillars have 5 or less pairs while sawfly larvae have 6 or more.

Rose slug damage on rose leaves
Rose slug damage on rose leaves. Photo by dmp2024

Check your rose bushes for rose slugs, a common name for at least 2 species of sawflies whose larvae may be feeding on your plants. One is thought to be native to the U.S. and the other accidentally introduced from Europe. Both were noticed as pests in the Boston area over 100 years ago and do similar damage to rose foliage.

The small green caterpillar-like larvae that may be ½ to ¾ inch long depending on the species skeletonize the leaves and only the veins remain. They can feed for several weeks if not controlled and move to the undersides of the leaves during the day making them hard to spot. One or two generations may be present each season, again depending on species. Mature larvae will pupate in the soil below plants, where they overwinter and will reemerge the following spring.

Hibiscus sawflies feed on members of the mallow family with the most common one in this area being the large-flowering perennial hibiscus. The green larvae are small, and also can be found on the undersides of leaves where they often go undetected until large leaf areas are consumed.

There are at least 3 species of sawflies that feed on azaleas in this area. The small green larvae have tannish heads but are hard to spot at first as they feed on emerging foliage. Keep an eye out for foliar feeding at the edges of the leaves. The larvae are less than ½ inch in length and feed until late June or early July. There is only one generation per year and these larvae will also drop to the ground to pupate and overwinter in the soil below plants.

Pine sawfly species seem to prefer Mugo, Scots and red pines although they can feed on others. Some are inadvertently introduced pests like the European pine sawfly. Since they were first noticed around 1925, they have become widespread pests. The larvae may be up to an inch long and is grayish-green with mostly darker parallel stripes. Red-headed pine sawfly larvae have red heads as the name indicates but has a yellow body with black spots.

Pine sawfly adults typically lay groups of eggs so multiple larvae hatch and feed in groups. They have a very distinctive defense mechanism when disturbed. Most curiously they rear up and ‘wave’ as you wave your hand over them. This does discourage insect, avian and vertebrate predators, at least to some extent.

Dogwood sawfly females can lay more than 100 eggs on the underside of their preferred grey dogwood host plant. Larvae can consume the whole leaf as they mature leaving only the large midvein. Young larvae are translucent and yellowish but develop black spots and become covered with a white powdery coating as they mature. Their appearance can make a gardener think there are two species of insects attacking plants rather than one. When mature, the larvae seek out an overwintering location with rotted wood on the ground being preferred.

Regardless of which species of sawfly is attacking your plants, options for control include hand picking, insecticidal soap, Spinosad or other insecticides labeled for sawflies. While Bacillus thuringiensis (BT) can be used for caterpillars in the Lepidoptera family, like cabbageworms and Eastern tent caterpillars, it does not work on sawflies.

If you have questions on identification or control of sawfly larvae or any other gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu

 

Keep your Perennials & Annuals Looking Fabulous All Season Long!

By: Heather Zidack, UConn Home & Garden Education Center

Geraniums and other flowers in a mixed container
Geraniums benefit from regular deadheading. They’re great for beginners because it is easy to tell the difference between new and spent flowers. Photo by H. Zidack

Hanging baskets, planter boxes and perennial gardens that are bursting with color are seldom planted in spring and left untouched until autumn. Deadheading, pruning, trimming and pinching are all techniques that gardeners can use to get that perfect look all season long. While it may be intimidating, this simple task can result in a huge visual impact with only a little effort. Through a series of pruning techniques, we manipulate our perennials and annuals to give us the most beauty we can get out of them in such a short season. It is important to recognize that cutting healthy flowers or shoots can help plants in the long term – no matter how much it may pain us as gardeners to do so.

Deadheading is a widespread practice where gardeners remove flowers that have gone by. One of the first things to become aware of is the difference between a bud and a spent bloom on the plant you are working on. Many gardeners will snip petunia buds, mistaking them for spent flowers. It is important to be vigilant with these cuts. Remember that your plant's goal is to reproduce, and they use flowers to do so. By removing the flowers, you are stopping the plant from producing seed and encouraging it to restart the cycle – meaning more flowers for you!

Some gardeners will select “self-cleaning” varieties of annuals that will shed their flowers without the need to deadhead all summer long. In general, these may not produce seed; therefore can easily restart the process themselves.

The whole practice of deadheading, pinching and trimming herbaceous plants can be boiled down to redirecting the plants energy into different purposes. Where deadheading helps to clean spent flowers, pinching will remove new buds before they bloom. If you want to encourage beautiful single stem cut flowers, for example, you may decide to pinch lateral (side) flower buds to force the plant to put all its energy into a single bloom at the top. Alternatively, pinching the terminal (top) bud will give you many smaller flowers on one stem, creating a fuller appearance.

This same principle applies to pinching shoots of herbaceous plants to make them fill out more. Cutting further down a stem will again remove that terminal bud and cause the plant to focus its energy on new shoots that come from nodes further down the stem. Think of how full your basil plants flush out when you harvest fresh herbs.

Torenia hanging basket
Torenia is considered a self-cleaning annual that is great for shade and is loved by hummingbirds! Photo by H. Zidack

Often, gardeners will notice that in mid to late summer their hanging baskets will start to look “tired.” They may notice prolific flowering on the ends that hang down, but often see that the center of the basket is not as full or may even be dying out. The first thing to check for is to make sure that you are watering them regularly. Because hanging baskets are suspended in the air and uninsulated, they will dry out faster. When you are trimming herbaceous plants for growth you can take one third of the plant volume away at a time, safely. Think about it as playing hair stylist! Cut back one third of the longest growth at the ends, and watch new growth come from the roots. It may also help your hanging baskets to remove any branches that have been shaded or dried out in the interest of “lightening” the growth that is hanging down.  Again, you may lose flowers for a week or two – but the result down the road will be beautiful!

For perennial gardens, June is a wonderful time to do some pruning as well. Cutting back early flowering perennials can encourage a second flush of flowering in some species. This works exceptionally well for plants like Salvia, Nepeta, and Lavender. Deadheading throughout the season will help plants like roses and Echinacea continuously flower. And pinching can help perennial mums form their shape for the fall.

Summer is a stressful time for plants! Disease, pests, and extreme weather can all contribute to a stressful environment. Our New England summers can promote these pressures with high heat and humidity levels. During these times, pay careful attention to your watering habits and adjust, as necessary. In times of drought or excessive heat, plants will use water faster for hydration and cooling, just like we do. Being aware of this can help you know when to check for water and help you be more diligent with your watering practices. Using a balanced, water-soluble fertilizer can also promote plant health and reduce stress in perennials and annuals. This is why it is great to fertilize after pruning and deadheading. If you need more information on trimming, watering, fertilizing, or any other gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu

Luscious Lemony Herbs

By Dawn Pettinelli, UConn Home & Garden Education Center

With summer almost around the corner, many of us are setting in vegetables and herbs in hopes of preparing delectable culinary delights as these plants mature. Aromatic herbs bring amazing flavors and zing to all sorts of savory and sweet concoctions. A citrusy taste complements many dishes and some may not be aware of the wealth of lemon-flavored herbs that are widely available and also easy to grow.

Lemon balm plants up close.
Lemon Balm in the garden. Photo by dmp2024

Long-lived lemon balm has been a staple in my herb garden for years. The attractive heart-shaped, scalloped leaves have a delicate scent when rubbed. Lemon balm is a hardy perennial native to Europe and has long been grown for its culinary and medicinal purposes. Fresh or dried leaves can be made into a calming tea that reputedly reduces anxiety. They can also be used in savory chicken dishes, to make pesto and even in baked goods. The lemon balm I grow is the species and it produces flowers that, like many members of the mint family, are loved by bees. A dilemma ensues as to whether to leave the blossoms for the pollinators and deal with the copious seedlings that pop up the following year, or cut the plant back to encourage more leaf production. Also, once lemon balm flowers, the leaves take on an unpleasant ‘soapy’ taste. Cultivars such as ‘Compacta’ are sterile, so no seeds are produced.

As long as it is grown in a well-drained soil, lemon thyme is another long-lived herb. Growing just 4 to 6 inches tall, it’s an attractive plant in the herb garden, as an edging plant or even as a front border plant in perennial gardens. There are green, golden, and variegated leaved cultivars. Sprigs of lemon thyme can be dried but I like to use them fresh in chicken or rice dishes. The pinkish flowers usually open in July and are a big pollinator draw. Like many herbs, the best flavor is obtained collected before flowering. Plants respond well to regular trimmings.

Lemon basil is an annual in our climate but easily grown from seed. Like all basils, it does best in a sunny, fertile site with adequate moisture. Plants also do great in containers. Leaves have a fresh lemony scent and taste with some hints of mint and spices. If growing from seed, one might want to try ‘Sweet Dani’, which was a 1998 All America Selection winner. Named cultivars such as ‘Mrs. Burns’ lemon basil usually have larger leaves than the seed grown types. Pinch out flower stalks as they form for better flavor or for a longer and more abundant harvest, cut off the top third of your plants about once a month. This encourages greater branching and leaf production. Lemon basil rice is my favorite way to use fresh leaves.

Lemon grass in a garden bed.
Lemon grass in the garden. Photo by dmp2024

A tender perennial, lemon verbena, is mostly grown as a container plant and overwintered indoors. Plants have an exceptionally strong lemon scent and if happy, grow quite vigorously. They can easily get 3 or 4 feet tall and will grow into a small tree in warmer climates. Lemon verbena is native to South America, so it enjoys full sun and hot weather. Leaves can be used in potpourris, teas, and sweets.

Another tender perennial best grown in a pot is the lemon scented geranium. There are several named cultivars with some, like ‘Mabel Gray’ and ‘Rober’s Lemon Rose’, having a stronger scent. Either buy plants or start from a friend’s cutting. The lovely scented wavy leaves can be placed in the bottom of a cake or loaf pan and then filled with batter and baked, imparting a lovely pattern and slight lemony flavor. They can be used fresh or dried for a variety of culinary uses and are also good in potpourris.

Those enjoying Asian cooking are likely already familiar with the rich flavor of lemon grass. While it is native to India and only hardy to zone 10 to 12, it is a pretty vigorous grower that would do well in either a garden bed or container. Reportedly plants may reach 2 to 3 feet in height by midsummer if kept well-watered. The leaves as well as the bulbous base of

the stem are used in recipes. A few stalks can be removed as needed for cooking. Cut back potted plants to 6 inches before overwintering in a sunny window indoors.

For more information about growing lemon scented herbs or on other gardening topics, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu or contact your local Cooperative Extension Center.

Tying Climbing Roses

By Marie Woodward, UConn Home & Garden Education Center

Climbing roses tied to a vinyl fence.
Photo by Marie Woodward

Climbing and rambling roses are a beautiful addition to any garden, adding height and depth to your outdoor space. These types of roses require proper training and tying to ensure that they grow in the desired direction, produce the most blooms and don’t become tangled or unruly.  Follow this guide on how to tie climbing and rambling roses to get the best results. 

Gloves, wire, hooks and pliers laid out on a table.
These tools are needed to train your climbing roses. Photo by Marie Woodward

For materials, one would need some twine or soft plant ties, a sharp pair of pruning shears, sturdy long-sleeved, thorn resistant garden gloves. Also, some wire and tools to secure to a trellis, fence or other structure may be necessary.

Climbing roses have two types of canes. Main canes are stems that originate from the base of the rose giving it its structure and support. They are also referred to as leaders. Lateral canes originate from the main cane. It is the lateral canes that produce the flowers and add volume to the shrub. In general, main canes are not pruned unless they are diseased or dead.

Before you start attaching the plant to a trellis, make sure that your rose is properly pruned. Removing any dead or diseased canes will encourage healthy growth. Cut back any wild or overly long shoots to create a manageable framework for tying. Starting with this step will allow for more control as you move through the process of tying.

Supportive wiring, better known as strain wires, helps to promote flowering. They hold the main canes at a 45–90-degree angle. These angles encourage lateral canes to flush and produce more abundant flowers.  

A rose cane tied to wire supports on a vinyl fence.
Attach your rose canes to strain wires with soft ties. Photo by Marie Woodward

If you're training your roses against a wall or fence, attach the horizontal strain wires to the structure, spacing them about 12-18 inches apart vertically and 5 feet apart horizontally.

 If you have a vinyl fence you can use vinyl safe hooks and secure the wire with a turnbuckle vertically, spacing them about two feet apart to avoid drilling holes in the vinyl material.

Using twine or soft plant ties, attach the rose canes to the support structure at regular intervals, starting about 1.5 feet from the ground. Tie them securely but not too tightly  You want to allow room for the canes to grow and expand. Avoid fishing lines or other rigid materials. Using the wrong ties or tying too tightly could lead to cane injury.

As the roses push new growth, continue to tie the new main canes to the support structure.  Continue to guide them in the desired direction, with those 45–90-degree angles as a guide.

Regularly check your roses and adjust the ties as needed.  Ensure that they remain secure but not too tight. Prune any wild or unruly shoots and remove any dead or diseased wood to keep your roses healthy and under control.

By following these steps and regularly maintaining your climbing rose, you’ll create a stunning vertical display that adds beauty and depth to your garden. While this guide provides good tips on for starting and maintaining younger climbing roses, older roses that have been neglected may need restorative measures. If you need more information on climbing roses or any other gardening questions, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu

Tips on Selecting a Flowering Tree

By Dawn Pettinelli, UConn Home & Garden Education Center

If there’s a spot for a spring flowering tree in your landscape, now is the time to look at the trees showing off their floral splendor. Do you find one or two particularly appealing. Take note of the various flower colors, tree shapes and sizes. Once you’ve selected an alluring flowering tree or two, do a bit of homework.

Many of the spring flowering trees have several cultivars and they may vary in flower color, leaf variegation, mature height and width, fall color and so on. Pick the one that fits your location. Will the plant be in sun or shade? Is it going to be positioned as a specimen tree or incorporated into a foundation planting or a border? Will it add multi-season interest with attractive foliage, fruits or seed pods, or interesting bark? What insect or disease problems is it prone to?

A redbud tree in flower on the UConn Campus
A redbud tree in flower on the UConn Campus. Photo by dmp2024

Redbuds (Cercis canadensis) are bursting with blossoms right now, at least on the Storrs campus. The extremely abundant, purple-pink peas shaped blossoms practically cover the tree. At maturity, trees reach about 20 to 30 feet tall with a slightly larger width, ending up in a roundish shape with a flatter top. After flowering, heart-shaped leaves develop while faded blossoms give birth to small, flattened legume seed pods that contrast nicely with the plant’s dark, scaly bark. Cultivars are available with white or more true pink flowers, variegated foliage, weeping forms and attractive fall foliage colors. Redbuds tolerate full to part sun and well-drained soil but avoid hot, dry locations for best establishment and flowering.

Dogwoods are a favorite of many. Their pink, white or red colored bracts dazzle especially in filtered sunlight. Dogwoods are native to the eastern and central United States where they are usually found as an understory tree. Most cultivars grow to about 30 feet in height with about the same width at maturity. The large 4-inch blossoms mature to form shiny red fruit much loved by birds. These exceptionally beautiful plants favor a cool, moist, acidic soil with adequate amounts of organic matter. Dogwoods struggle when faced with heat stress, drought, and pollutants so site carefully.

Another flowering tree that also does best in more natural settings, especially those with moist soils is our native shadbush or serviceberry (Amelancher canadensis). The name, shadbush, comes from the fact that this plant typically blooms when the shad return to fresh water to spawn, usually right about now. This plant can be grown as a single stemmed specimen or a multi-stemmed large shrub. Mature trees reach about 20 feet in height but there are shorter, more shrub-like cultivars. Shadbush sports white flowers in 2-to-3-inch racemes. Dark fruits are attractive to many animals plus both the gold autumn foliage and gray bark are very attractive.

Carolina silverbells in flower.
Carolina silverbells in flower. Photo by dmp2024

A standout for me this time of year is Carolina silverbells (Halesia carolina). A multitude of white, bell-shaped blooms adorn the branches of this 20-to-40-foot tree. Although it is native to southeast U.S., it is hardy to zone 5. Autumn color is not notable, but the tan 4-winged fruit persist well into the winter and stand out against the stark winter landscape and silvery grey bark. Be sure to check out ‘UConn Wedding Bells’, a very floriferous cultivar discovered by UConn Plant Science professor, Dr. Mark Brand. It has a smaller, rounder form with flowers larger than the species.

The star magnolia (M. stellata), as its Latin name implies, is definitely a stellar landscape plant. Gorgeous, lightly fragrant 3-to-4-inch blossoms grace the dense cluster of stems. Mature plants reach up to about 20 feet with a slightly narrower width. Plants do produce red fruits but most drop before they mature. I was delighted to find a seedling after I lost the parent tree in that late October snowstorm we had a number of years ago.

Other worthy spring flowering trees to consider include the flowering crabapples and cherries that have many exciting and lovely cultivars. A great place for information on woody plants is the UConn Plant Database (www.plantdatabase.uconn.edu). If you need more information on selecting a tree or any plant for your landscape or on other gardening topics, feel free to contact us, toll-free, at the UConn Home & Garden Education Center at (877) 486-6271, visit our website at www.homegarden.cahnr.uconn.edu or contact your local Cooperative Extension center.

 

Eastern Tent Caterpillars

By Pamm Cooper, UConn Home & Garden Education Center

Eastern Tent Caterpillar Tents in a tree

Eastern tent caterpillars, Malacosoma Americanum, are native to North America and are noticed mainly because of the silken tents they build in the forks and crotches of trees in early spring. While most tents are found on black cherries, they can also be found on other trees such as apple and crabapple. They are readily visible since tents are constructed before leaves fully expand. There is only one generation per year.

These caterpillars are hairy and dark when small, and later instars have two yellow lines along the back. A white medial stripe goes along the sides of the body, and this is flanked by two yellow lines. There are blue blotches along its side as well. Bottom hairs on the body are rusty brown. Forest tent caterpillars are also hairy, but they do not make tents, and their bodies

are blue with white dots on the back. Handling should be done with gloves on as some people may have sensitivity to the hairs.

Egg masses are black, laid on small branches of host trees the previous year, and the egg mass rings around the branch. Sometimes they are mistaken for small black knot galls. 150-300 eggs may be in each egg mass. Caterpillars typically hatch as black cherry leaves begin to expand the next spring. Caterpillars feed on leaves and buds and rest communally by day in the nests they construct from silk.

While they can almost defoliate small trees, these caterpillars usually have completed their feeding stage in time for the trees to put out new leaves by early summer. The more tents there are on small trees, though, the greater number of caterpillars there are, so damage will increase.

While protected from many predators while inside the tents, there are birds that will tear the tents apart to feed on the caterpillars inside. Both the black-billed and the yellow-billed cuckoos are known for their ability to do this, and native vireos will also seek out and rip apart the tents.

Mature caterpillars leave the host plants in early summer in search of suitable sites to pupate within a silken cocoon they will spin. Moths emerge later that year. The moths have a fluffy light brown body, and the wings have three bands with the center being narrower than the outer bands and a lighter brown in color. The center band is bordered on both sides by thin, creamy bands.

Eastern Tent Caterpillar Tents in a tree

Occasionally, eastern tent caterpillars have outbreak years where large numbers of the tents can be seen on the same tree. Fresh buds may also be consumed if trees are severely defoliated. When found on residential properties, tents can be swept apart by rakes or brooms, exposing caterpillars to predators, or knocking them off the trees. If warranted, foliage can be sprayed with a biological product called Bacillis thuringiensis subspecies, Kurstaki, or BtK, which only harms caterpillars and not other insects. Caterpillars will ingest the product as they feed on the foliage.

Most healthy trees can tolerate severe defoliation from eastern tent caterpillars. If concerned, look for egg masses in the winter on trees that had been damaged the previous spring. Remove them, if possible, or crush them, or prune the branch off below where the egg mass is found. Or let them be if the trees appear to have recovered. Letting nature take its course with native insects on native trees can often benefit birds and other predators. Do not confuse them with the notorious gypsy moth caterpillars which do not make silken tents or nests of any kind.

If you have a question about tent caterpillars or other gardening topics, contact the UConn Home & Garden Education at (877) 486-6271 or www.homegarden.cahnr,uconn.edu or your local Cooperative Extension Center.