Snap beans grow best in full sun (they are tolerant of light shade) in a moist, well-drained, friable and moderately fertile soil.
Sandy loam soils which are loose and warm rapidly in spring are preferred, but beans can be grown successfully on heavier clay or organic soils provided the soil is properly prepared and well managed. This may include mixing in some coarse sand to loosen the soil to improve drainage and aeration.
Snap beans make best use of fertilizers if the pH is 6.0 to 6.5. When lime and/or fertilizer is applied, till it six to eight inches deep just prior to planting. Break up large clods of soil and rake the area smooth.
Snap beans are the most popular bean, and many of the varieties are stringless. Beans have a short growing season and are harvested when the pods are immature. The snap bean is a member of the legume family and has the ability to fix atmospheric nitrogen in its roots. However, beans do not remain in the ground long enough to be effective in producing nitrogen-fixing nodules.
Snap beans are either bush or pole types. Bush types are self-supporting plants that grow one to two feet high, while pole types produce vines that require support such as stakes or a trellis.
Snap Bean Varieties Suitable for Connecticut
|Bush-Green||Bush-Green Bush Blue Lake, Greensleeves, Provider, Tenderpod, Greencrop, Roma, Derby|
|Bush-Yellow||Bush-Yellow Slenderwax, Goldcrop, Golden Butter Wax, Gold Rush|
|Pole||Pole Romano, Blue Lake, Rust Resistant Kentucky Wonder,
Snap beans are a warm season crop that grows best when the mean temperature is between 70º and 85ºF. Temperatures that are too high can cause plants to drop blossoms. Germination is delayed when soil temperature is below 65ºF. In most parts of Connecticut, planting of snap beans can be done successfully in mid- to late May.
The bush-type varieties are usually planted in rows. For single rows with 18 to 30 inches between rows, the seeds are sown one to two inches apart, and seedlings are thinned to two inches apart. For wide row plantings that are 18 inches wide, the seeds are placed three to four inches apart in all directions.
The pole varieties are planted in rows two to four feet apart with seeds spaced one to two inches apart. Use stakes or a trellis to hold vines from falling to the ground. Pole varieties are also planted in hills three feet apart in all directions. Sow six to eight seeds in each hill and thin to three to four strongest plants to a hill.
Snap beans have large seeds which are sown 1 to 11/2 inches deep. Successive plantings of bush-type varieties at two-week intervals can prolong the harvest season.
Weeds are controlled easily in the seedling stage by shallow cultivation. Do not cultivate too deep because bean roots are close to the surface.
A two- to four-inch layer of mulching material such as straw, weed-free hay, mulch, lawn clippings or other loose organic material can be effective against annual weeds if it is applied to weed-free soil. Black plastic stops all weed growth and may hasten bean growth by warming the soil.
Beans are sensitive to both dry and wet conditions. Too much or too little water can cause beans to drop their flower buds or pods. Keep the soil evenly moist. An inch of water per week is needed during the growing season. This will moisten the soil to a depth of six to 12 inches.
Snap beans are harvested as immature pods before the seeds are well developed. At this stage, they have the best flavor and nutritional value. Beans must be picked two times a week to ensure a continuous harvest. If pods are allowed to mature, the plant will stop blooming.
Insects, Diseases and Other Pests
Snap beans are attacked by many insects and diseases and their damage can be serious at times. However, problems are best controlled by some preventive measures such as planting disease-resistant varieties or disease-free seeds, removing and destroying all diseased plants in and near the garden, using crop rotation, not handling plants when the foliage is wet, and keeping the garden and surrounding areas free of debris and weeds.
Chemical control is another way to combat diseases and insects. However, it should be used only after all other methods have failed.
Brown to black sunken circular spots.
Under moist conditions, spots may
have pink color.
Dark reddish-brown to black area on
Elongated rust colored lesions
|Grow resistant varieties.
Till in debris in the fall.
Apply fungicides at flower initiation,
late flowering and pod fill stages.
Small, water-soaked areas developing
into larger, reddish-brown areas.
Stems and pods:
Deeply sunken lesions surrounded
by reddish-brown tissue.
|Plant western-grown seed.
Stay out of garden when plants are wet.
Till in debris in the fall.
Apply fungicidal sprays when disease is noticed
|Mosaic viruses||Yellow mottling of leaves.
Deformed leaves and stunting of plant.
Blossoms may drop.
Vectored by aphids.
|Plant resistant varieties.|
|Powdery Mildew||Powdery white growth on leaves, stems
and occasionally pods.
Affected parts often shriveled and
|Grow resistant varieties.
Provide adequate air flow.
Apply sulfur fungicides weekly during
periods of high humidity.
|Rust||Small, whitish, slightly raised pustules
on the underside of the leaves turning
a reddish-brown. These discharge the
rusty colored dust-like spores. More of
a problem in hot, humid weather with
heavy morning dew.
|Maintain good air circulation.
Apply a fungicide when weather
conditions are favorable for disease development. Weekly applications
may be necessary.
|Water soaked spots appear on stems,
leaves and branches about seven days
A white cottony mass develops in
which small black hard bodies appear. Leaves yellow, brown and fail off.
|Provide good air circulation in
Apply fungicide at first bloom.
|Mexican Bean Beetle||About 1/4" long, coppery brown color.
Eight black spots on each wing.
Small yellow eggs. The larva is a
yellow spiny grub usually found on
the underside of leaves.
|Clean debris from and near the
garden where the adults
|Aphids||Small green, yellow or black sucking
insects found near the new growth.
Heavy feeding causes curling on the
foliage and presence of honeydew
which turns black from sooty mold.
|Apply insecticidal soap.|
|Leafhoppers||Small light-brown to gray insects
about 1/8" long which hop when
Capable of transmitting viruses.
|Control weeds in and near the garden.
Apply insecticidal soap when insects
|Very small, light-colored or reddish.
Small white spots on leaves where
mites have fed. Heavy feeding damage
will cause the foliage to brown.
Webs are present when mite
populations are high.
|Apply insecticidal soap when insects
Despite good cultural practices, pests and diseases at times may appear. Chemical control should be used only after all other methods have failed.
For pesticide information or other questions please call toll free: 877-486-6271.
Revised by the UConn Home and Garden Education Center 2016
Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, the Dean of the College, Cooperative Extension System, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer and program provider. To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, Stop Code 9410, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964Issued in furtherance of Cooperative Extension work, Acts of May 8 and June 30, 1914, in cooperation with the U.S. Department of Agriculture, the Dean of the College, Cooperative Extension System, University of Connecticut, Storrs. The Connecticut Cooperative Extension System is an equal opportunity employer and program provider. To file a complaint of discrimination, write USDA, Director, Office of Civil Rights, Room 326-W, Whitten Building, Stop Code 9410, 1400 Independence Avenue, SW, Washington, DC 20250-9410 or call (202) 720-5964.