Cucumber is an annual warm-weather crop that is easy for some gardeners to grow, yet others find nearly impossible to work with. They require only a short growing season of usually 55-65 days from planting to harvest and can be harvested for a month or more. This makes them ideal for our 70-day growing season.
If the right variety is picked, cucumbers can be grown in just about any part of the United States. For specific planting dates in your area, check with your local extension office. They should also be able to suggest a good variety for your area, and if you have a longer growing season, they can help you with a schedule for succession planting if you wish.
Planning to grow Cucumber
Picking A Good Cucumber Variety
The most common varieties are:
- Early Pride Hybrid: a 55-day variety that grows straight up to 8½”
- Cherokee: a 55 day variety that is smooth skinned and good for pickling
- Straight Eight: a 58 day variety
- Bush Champion: a productive 55 day variety that grows up to 11” cucumbers on compact vines, which makes it good for containers
- Tasty Green Hybrid: a 62 day burpless variety that grows up to 10”
- Sweet Success: a 58 day variety that is thin-skinned, seedless, and grows up to 14”
For an heirloom variety:
- Double Yield: a very productive 55-day variety that grows to 8”
- Lemon Cuke: a 58-64 day variety that is yellow-skinned and almost round
- Sumter: a 56-day variety that is good for slicing or pickling
- White Wonder: a 60 day variety that is a creamy-ivory and good for pickling or slicing
Advanced gardeners may want to familiarize themselves with gynoecious and parthenocarpic varieties.
Some of the most disease-resistant varieties of cucumber are gynoecious varieties. Areas that have a lot of problems with cucumber disease may be interested in these varieties. Gynoecious varieties produce only female flowers, and a second variety that produces male flowers is required for pollination, and for fruit to set.
Seed suppliers will add one or more pollinator seeds (often marked with red or pink dye) in a package of gynoecious seeds. Sometimes, however, they do not. Read descriptions carefully before ordering, and make sure your dyed seeds are planted and healthy in order to grow cucumbers.
Victory Hybrid is a top-performing seed of gynoecious varieties.
Parthenocarpic varieties also produce only female flowers, however, they do not require pollination from a male flower. In fact, some will actually produce fruits that are distorted if pollination occurs.
These varieties are designed for greenhouse growing, where insects are not present for pollinating.
I grow the Double Yield, and am trying the White Wonder this year as well.
Preparing The Soil For Cucumbers
Cucumber plants like well-drained soil that is rich in organic matter in a sunny location. They do best when allowed to grow in a loose, rich soil that holds moisture well.
Make sure to work the soil deep and thoroughly where you will plant your cucumbers so they can immediately begin to form their extensive root systems. When starting your season, the top of the soil should be loose for a foot or more.
If you have an area with poor soil, add up to 4 inches of compost to the area and work it in well, allowing it to mix and sit before the time to plant comes.
When it is time to plant, put a shovel of well-rotted manure at the base of each hill or row you prepare.
- Sow 2 or 3 radish seeds in your cucumber hills and leave there even after they seed. radishes repel cucumber beetles.
- Grows well with beans, lettuce, cabbage family, peas and tomatoes. Learn about growing tomatoes here
- Cucumbers repel raccoons, so plant near your corn. (My husband just informed me that it would be more beneficial to just throw cucumbers at them). Corn also repels cucumber beetles.
- Marigolds repel cucumber beetles, aphids and flea beetles.
- Tansy repel aphids, cucumber beetles and cutworm.
- Nasturtiums repel aphids, flea beetles, cucumber beetles and cabbage loopers.
- DO NOT plant near potatoes as cucumbers encourage blight in late potatoes.
- Aromatic herbs cause slow growth to cucumbers.
- Don’t plant next to members of the same Genus. If one plant gets infected or infested by a pest, it will be easier to transfer to others. They also compete for the same nutrients in the soil.
How To Grow Cucumbers From Seed?
Because cucumbers are highly sensitive to frost, never place them in the soil until it has warmed—at least 60, 70 is best. A general rule is to plant them 2-3 weeks after your average date of last frost. Make sure to give them protection from the cold if there is any danger of cold weather.
Most seed catalogs suggest sowing 4-5 seeds in each hill. Hills should be spaced 6 feet apart, while bush varieties may be placed only 3 feet apart. Once plants start to develop, thin all but the 3 strongest in each hill.
I must confess, that I generally just plant 3 in a hill if I’m letting them sprawl along the ground, and never thin them.
If you live in a longer growing season area, start a second crop 4-5 weeks later. If you live in the Deep South however, you should wait to plant until 80-90 days before your first fall frost.
If you will start your seeds inside, then time them to about 3 weeks before they will go outside. Although many resources state that starting cucumbers inside is a successful endeavor, I have found very low success rates with transplanting perfectly healthy cucumber starts into a garden, no matter what soil or what zone I have gardened in. If you have trouble transplanting cucumbers, you have company.
Transplanting Cucumber Plants
If you will be transplanting cucumber starts into your garden, take extra care to harden them off before doing so.
If you have the availability of a cold frame, place them in there for a week to harden them off.
Intermediate gardeners may want to try planting a second crop of cucumbers about 4 weeks after the first set. Plant this second crop where you have harvested a spring crop (like broccoli).
Growing Cucumbers In A Container
Bush and compact varieties do best in containers. If possible, start your cucumbers directly in the container they will live in, making sure it is at least 18 inches deep to allow for root development.
Container cucumbers do best when given trellis support to climb on. Trellis should be in place as soon as seed is sown into the pot.
An advantage to container planting is that plants can be moved to a protected area at night once temperatures start dropping at night, and then back outside during the heat of the day.
A disadvantage of container planting is that your cucumbers will need more frequent watering.
Taking Care Of Your Cucumber Plants
Cucumbers have a 90% water content, and as such, will show signs of moisture stress while forming if not given enough water. This will lead to skinny portions of the fruit during development in times of drought, and make cucumbers bitter. Make good use of mulching to maintain water moisture if you are able.
While some cucumbers may grow along the ground, trellising them can often lead to more productive plants and healthier fruits.
As soon as your cucumber starts to vine, start training them on the trellis. You will be able to grow more fruit in less space. Cucumbers will grow straighter as they hang from their vines. They will be easier to find and have fewer disease problems.
As your main vine elongates, pinch off the first few side shoots that would otherwise spread sideways.
Be careful to pay even more attention to water needs for cucumbers that are trellised, as the foliage will be more exposed to the sun and air, thus making plants more prone to drought stress.
As your season ends, pinch back vines to encourage existing fruits to mature before frost hits.
Cucumbers are a member of the squash family, and just like traditional squash, the male flowers will be produced first on each vine, followed by female flowers. Flowers are yellow, and the female flowers will have small fruits attached to the base.
In order for pollination to occur, insects must carry pollen from the male to the female plants.
When it’s time for pollination to occur, you will need to uncover your cucumbers so that insects can do their job if you have them under a row cover. During times of insect inactivity (cloudy and cool days) hand pollination may be needed.
Cause of Bitter Cucumbers
Bitterness is produced by a taste deterrent compound named cucurbitacin found in plants of cucumbers. The bitter cucumber can be caused by genetics, growing conditions, or old age. There are a few varieties that never become bitter.
Cool-weather during development produces bitter fruit. The moisture stress and drought condition during development can also make cucumbers bitter.
If you get bitter fruits, remove the skins as soon as they are picked, and slice off the flesh under the peel at the stem end. Use these cucumbers right away for slicing and eating to make the most of them.
When And How To Harvest Your Cucumber
Once a vine succeeds in getting a cucumber to mature seeds, the vine will stop producing and die. For this reason, it is important that you watch your cucumber plants carefully and remove all cucumbers as soon as they are ready.
Those on trellises will be easier to locate and remove. Vines allowed to sprawl on the ground must be checked more carefully. Pick up your leaves and check under them often when fruits start to mature.
If you’re unsure if your cucumber is ready, look for the flower at the end. When it drops off the blossom end, it’s ready to be picked. If a cucumber has been allowed to turn yellow, it is too ripe.
Vines can produce for a month or longer, although sometimes productivity will decrease. This can simply be due to age, or it can be from disease, certain insects, or maturing fruits that send “stop” signals through the vine due to a lack of cucumbers being picked in time.
If your cucumber has spines, they are ready when dimpled areas around those spines have filled out.
For pickling varieties, start picking fruits when they are 2-4” long. For slicing and salads, pick your cucumbers between 6-8” long, remembering that younger cucumbers will be a better quality. European varieties may grow up to 10” long.
Pests & Diseases
Cucumbers are vulnerable to several serious diseases, including mildews, scab, anthracnose, and bacterial wilt.
Your first step in defense will be to thoroughly research your variety of cucumber. Some grow with only special care when special needs are met. Next, remember that an ounce of prevention is worth a pound of cure. Prevent diseases as much as possible.
If you can avoid damage from cucumber beetles while vines are young, and keep fruits off the soil with trellises, bacterial wilt is much easier to control once the vine has developed.
Other problems with cucumbers can be avoided by paying close attention to water needs and making sure your plants are warm enough.
In short, if you can remember to grow cucumbers in only warm weather after the soil has warmed, pay close attention to make sure it has enough water, and pick your cucumbers often as soon as they are ripe, you’ll be on your way to enjoying your own, homegrown cucumbers.
Cover your rows at planting time to protect them from cucumber beetles. Plants may be sprayed with kaolin as the crop develops to deter cucumber beetles if unable to be covered. Some common cucumber pests include
- Cucumber Beetle: holes chewed in the leaves, leaf stalks, and stems by yellow-green beetles with black stripes or spots. Plants may wilt and die.
- Bacterial Wilt: A few leaves wilt and dry and may be chewed. Wilted leaves usually recover at night but then wilt again on sunny days and finally die. Fruit shrivels. A small home test can be done by cutting a wilted stem near the base of the plant and squeezing out the sap, watching for it to be milky white. Touch a knife to the sap and withdraw slowly. Look for a white ooze that strings out in a fine thread as you withdraw the knife. Remove and discard all infected plants promptly.
- Anthracnose: Yellow, water-soaked areas on leaves that enlarge rapidly, then turn brown and dry. The spots then fall out leaving holes in the spot. Whole leaves and vines die. Large fruit is spotted with sunken, dark brown circular spots. Pinkish ooze may come out. Small fruit shrink and die. This disease is most prevalent in humid or rainy weather. Prevent by growing varieties that are resistant, avoid overhead watering, clean up crop residue or turn it under the soil at end of the season. Treat infected plants with a commercial, disease control chemical. Follow directions
- Powdery Mildew: A white powdery growth covers the upper surfaces of the leaves. Areas of the leaves and stems turn brown, wither and die. Fruit may be covered with white powdery growth. Prevent by growing varieties resistant to powdery mildew.
- Many other viral and fungal diseases. The best prevention is crop rotation, proper clean-up, pest management, and good ventilation.
- Cucumbers grow best in full sun, fertile and well drained soil. They like their soil to be high in organic matter with almost neutral pH. Be sure to change location of your plants every year. Rotating their location helps reduce risk of soil diseases and better soil that has the nutrients they need.
- Sow cucumber only when the soil is warm. The tenderest greenhouse cucumbers are grown in 80ºF weather. Sometimes, warming the soil with a sheet of black plastic before planting can give you an early start on planting cucumbers.
- If sowing seeds indoors before last frost, avoid planting in flats because cucumbers don’t like to have their roots disturbed.
- The secret to a heavy, long production is to pick often! If you pick the fruit when it is young, it tells the plant to produce more to make more seed for future generations, waiting until the fruit is fully mature and turning yellow, tells the plant that it’s job is done. So pick those cucumbers as soon as they are large enough to be used.
- Harvest cucumbers when young for the best flavor and crispness. Pick moist, green pods that are tender, and just slightly filled out. If your growing beans for shelling, you can leave them on the vine to dry, but otherwise pick as soon as they are ready or the vine will stop producing.
- Plant your first crop of cucumbers in May for harvesting in July and August, and your second crop of cucumbers in June for harvesting in August and September. When plants get too old, production and flavor are affected.
- Always protect from cold and frost. If a hard frost is predicted, always pick all mature fruit and cover small fruit and foliage with several layers of newspaper.
- Remember that cucumbers produce both male flowers (straight stem below flower) and female flowers (small fruit below flowers), when plants are young, they often produce much more male fruit than female. Lack of fruit means lack of pollinated flowers.