Cucumber
Cool, crisp, crunchy cucumbers are a summer garden essential! Tasty cucumbers will trail and climb along any given trellis, but we also offer bush and compact varieties that are great for container planting.
Plant care & info
Cucumbers require full sun (at least 6 hours of direct sun) and rich, well‐drained soil. Prepare the planting area by mixing 3‐4” of composted manure and lime into the top 6‐10” of the soil. Mix in an all‐purpose granular fertilizer in the bottom of each planting hole.
Cucumbers thrive in warm weather and are best planted outside from the end of May through the first week of July when soil temperatures are in the 60s or above. Space groups of seeds 3‐4’ apart in hills or raised beds. Sow 4‐6 seeds 1⁄2” deep and cover them with a thin layer of soil. Once seeds have germinated, pinch off the weakest ones, leaving only the strongest one or two.
You can start seeds indoors in May, 3 weeks before the desired transplanting date. Cucumbers do not like root disturbance, so we recommend planting start seeds in pots which can later be planted directly in the ground. Water in with a diluted liquid seaweed or B1.
Keep new beds well weeded and slightly moist. You can cover new plantings with floating row cover to prevent cucumber beetles and other insects. Remove row covers when plants begin to flower. Organic mulches can help heat the soil and retain moisture. It also helps to trellis your cucumbers to save space and prevent diseases.
You can extend your harvest season by first planting in late May, and then again 4 weeks later in June.
How much water your plants will require depends on the soil and weather. Cucumbers want average, evenly moist watering during the growing phase. Once they begin to flower and set fruit, they need heavy watering. Water deeply when the top 2” of the soil is dry to allow for even and tasty fruit development. Cucumbers are more than 90% water, and water stressed fruit will be bitter and/or have skinny portions. Drip irrigation is the best way to provide even moisture and while having fewer disease issues.
Cucumbers are heavy feeders. Don’t forget to mix an all‐purpose granular fertilizer into the bottom of each hole before planting. Side dress plants after 3 weeks with composted manure or all‐purpose granular fertilizer.
Cucumbers are ready to harvest when the flower drops off the end of the fruit. It is important to keep picking your cucumbers to maximize production. This could be a delightful daily task! Generally speaking, pickling cucumbers are picked at 2‐6” long and slicing cucumbers at 6‐10” long.
Good gardening practices—crop rotation, drip irrigation, proper planting time, floating row covers, and removal of entire plants when harvest is done—all help prevent many pest and disease challenges.
- Flowers may not form fruit for a variety of reasons. Most cucumbers have separate male and female flowers. Often, the first flush of flowers are only males. Other times, you may have female flowers with tiny fruit that never develop and fall off. When this happens, lack of pollination is the issue. Cool, cloudy weather can also deter pollinating insects from visiting your plants. Hand pollinate with a paint brush to help the fruit set. A few varieties require a second, different variety for pollination. Orient Express and Cool Breeze are two varieties that require a pollinator.
- Anthracnose appears as yellow and brown spots on leaves, coupled with dark streaks on stems. It is a fungal disease that can be controlled with Serenade and copper sprays.
- Angular leaf spots appear as geometric, yellow and/or brown leaf spots which eventually leave holes. It is a bacteria spread by splashing rain. Remove infected areas, avoid overhead irrigation, and use plastic mulches to prevent infection.
- Bacterial wilt is a virus which causes either leaves or the whole plant to wilt. Cut stems will exude a thick ooze. There is no cure, but using floating row covers help prevent cucumber beetles which transmit the virus.
- Cucumber Mosaic virus appears as yellow, mottled, curling leaves. As with other viral diseases there is no cure, and infected plants should be removed and destroyed.
- Downy mildew appears as splotches of angular yellow or brown spots that are purplish on the underside. Infected leaves should be removed. Spread of the infection may be controlled with Serenade.
- Powdery mildew will occur on all cucurbit crops at some point in the season. It may first appear as powdery white spots on leaves and stems or coat entire leaves. The fungus spreads in warm, dry weather. Pick off infected areas and spray with copper or Serenade to prevent the spread of the fungus.
- Cucumber beetles may chew seedlings or leave a lacy pattern in leaves of larger plants. They transmit bacterial wilt. Use floating row covers crop until flowering begins. Beneficial nematodes can kill the larvae, lacewings and ladybugs will eat the eggs, and rotenone and pyrethrin can help control populations.
- Melon aphids cause leaves to curl, distort, and turn yellow. Often, white aphid skeletons and colonies of apple green bugs are visible on the growing tips and underside of leaves. There are numerous control methods to control aphids, such as ladybugs and insecticidal soap.
Ideally, crop rotation has a 3 year cycle. If a small garden has you thinking a 3 year rotation is not for you, you can still plant different families in different places each year, or grow mixed plantings in your whole garden. Rotation is more important to some plant families than others. The most important ones to move are brassicas, cucurbits, and solanums (in order of priority).
