How to Grow Cucumbers: Planting, Growing, Harvesting
Cucumbers are a hot-weather crop, perfect for in ground gardens as well as containers. Rich in antioxidants, vitamins K, B, and C, and minerals such as magnesium and potassium, they’re not only a healthy snack, but their anti-inflammatory properties also make them good for your skin. And if you’re looking to become self-sufficient and start growing your own food, adding cucumbers to your list of vegetables is definitely a must.
In this guide, we’ll explain how to grow cucumbers from seed, discuss the importance of correct watering and manual pollination, and dispel a common myth about which plants to grow with cucumbers. We’ll also take a look at the many cucumber varieties, and help you pick the best types to grow in your garden — and even your apartment.
When it comes to cucumber varieties, many gardeners believe that there are only two types: bush and vining cucumbers. However, this is a remarkably versatile crop, available in a wider range of hybrids and cultivars than you probably imagined.
Let’s take a look at the main cucumber types you’ll find in cultivation.
The best-known variety, slicing cucumbers are designed for slicing and eating fresh. They usually grow up to 8 inches long (20 cm), have a thin skin, few seeds, and a crunchy texture.
Popular varieties: English cucumber, Marketer, Sweet Slice, Diva.
These cucumbers were specifically designed for pickling. They have thicker skin, usually with small, spiky bumps, an irregular shape, and noticeable bitterness.
Popular varieties: Cornichon, National Pickling, Bush Pickle, Kirby cucumbers.
All cucumbers contain cucurbitacin, a substance that gives them a mild bitterness and… well, makes you burp. However, burpless cucumbers contain lower levels of cucurbitacin, which also gives them a milder taste and makes them easier to digest.
Popular varieties: Muncher, Burpless 26, Sweet Success, Summer Dance.
Unlike vining cucumbers, bush varieties have a compact growth size and prefer sprawling on the ground rather than climbing. Bush cucumbers also produce smaller fruit and are ideal for growing in pots.
Popular varieties: Salad Bush, Bush Pickle, Bush Champion, Spacemaster.
The most diverse group by far, Asian cucumbers come in a wide range of shapes, sizes, and colors. Here are some great varieties and cultivars you can try growing.
Slicing varieties: Japanese cucumber, Suyo Long, Korean cucumber
Round cucumbers: Lemon cucumber, Crystal Apple, Dosokai.
White and yellow cucumbers: Itachi, Poona Kheera, Chinese Yellow, Malabar cucumber.
What makes parthenocarpic cucumbers unique is the fact that they don’t require pollination. As a result, they’re a great pick for gardeners who wish to grow cucumbers in a greenhouse or indoors.
Popular varieties: English cucumber, Beit Alpha, County Fair 83, Diva.
When Is the Best Time to Plant Cucumbers?
Cucumbers are tropical plants that need warm soil to germinate and temperatures between 75°F and 85°F (24°C to 29°C) to grow. If you’re planting cucumbers outdoors, the best time to sow them in the garden soil is in mid to late spring. Or, to get a head start in your growing season, start them indoors in late winter or early spring.
If you’re not sure when to plant cucumbers depending on your hardiness zone, check out our planting calendar. This will ensure that your cucumbers have plenty of time to grow and produce a bumper crop.
Where Should You Plant Cucumbers?
Cucumbers grow best in full sun. Plant them in a part of your vegetable garden that receives at least 6 hours of sunlight per day — although 8 hours would be ideal. Providing your cucumbers with enough sunlight will guarantee that your plants grow productive vines that yield a large cucumber crop. Also, it protects your cucumbers from fungal diseases such as powdery mildew.
How to Plant and Grow Cucumbers
Cucumber plants need four things to grow: warm temperatures, lots of sunlight, frequent watering, and well-draining, nutrient-rich soil.
Let’s take a closer look at everything you need to do in order to grow delicious cucumbers in your own garden.
Preparing the Soil
Cucumbers grow best in nutrient-rich, slightly acidic, well drained soil. Drainage is essential for these moisture-loving vegetables, and it’s the first step in protecting your crop from root rot. At the same time, you want the soil to retain some moisture, otherwise, your cucumbers will struggle to grow.
Start by digging the soil to a depth of at least one foot (30 cm), then work in plenty of well-rotted compost or composted manure. Cucumbers need fertile soil to sustain their vigorous growth. If you can, aim for a 1:1 ratio of garden soil and compost. This will provide them with the nutrients they need and facilitate drainage and moisture retention.
Cucumbers can tolerate a soil pH as low as 4.6 but will grow best in a pH ranging from 6.0 to 7.0. Use a soil test kit to check if your soil is more acidic or alkaline, and add some limestone if the pH is higher than 7.0.
Sowing Cucumber Seeds
Cucumber seeds need a soil temperature of at least 68°F (20°C) to germinate. In most growing zones, this means that you can only sow them outdoors in late spring, which greatly reduces the length of your growing season. To give yourself a head start, it’s best to grow seeds indoors, then transplant them into the garden once the weather gets warmer.
Soak the cucumber seeds in lukewarm for 12 hours before planting them. If you’re starting them indoors, sow the seeds in 3-inch wide (7.5 cm) compostable peat pots, to reduce the risk of damaging the seedlings when transplanting. Fill each pot with a well-draining potting mix, and plant one seed per pot, ½ an inch deep (1.2 cm). Water well, and keep the pots on a warm, sunny windowsill.
If you’re planning to sow cucumber seeds directly in the soil, wait at least 2 weeks after the last frost. Sow the seeds 1 inch deep (2.5 cm) in a sunny part of your garden, and water them well. To speed up germination, cover them with an upside-down jar or glass, which will also protect the emerging seedlings from a surprise frost.
For cucumber vines trained to climb on a trellis, space plants about 24 inches apart (60 cm). If you’re not going to grow your cucumbers on supports, allow at least 4 feet (1.2 meters) between each plant.
You can transplant cucumber seedlings to the garden soil when they are at least 4 inches (10 cm) tall and when they have at least 2 pairs of true leaves. Handle each plant carefully, to avoid damaging the roots or breaking the stems. If you’re using peat pots, simply use the trowel to dig a hole the size of the pot, and place the entire pot in it, without removing the seedling. The pot will decompose while in the soil, and the roots will have no trouble digging through it.
If you live in an area that’s likely to experience cold snaps even in mid to late spring, it’s worth investing in plant cloches. Cucumber seedlings are deathly sensitive to frost, and covering them with a cloche is a great way to provide them with warmth and humidity. Keep them covered with a cloche during the night, until early summer, or until any chance of frost has passed.
Most cucumbers are vining varieties, which enjoy climbing and send out vigorous vines as they grow. Of course, you can also allow your cucumbers to sprawl on the ground. But growing them on a trellis or frame takes up less space, provides air circulation, and keeps the ripening fruit off the damp soil and away from pests.
Set your supports in the ground before or soon after planting your cucumbers, to avoid damaging the roots. You will need to train your cucumber vines to climb by manually placing the young vines on and around the support. As the vines grow, they will send out tendrils which will keep the plants upward, so you don’t need to tie them with string.
Cucumbers are thirsty crops that need to be watered deeply and regularly. They do not tolerate drought, but they are also sensitive to overwatering and having their leaves wet. Overhead watering can spell disaster for your crop, especially in hot, humid weather.
The easiest way to ensure that you water your cucumbers correctly is using a drip irrigation system on a timer. Run it once a week for an hour, preferably in the morning, or twice a week if the weather is very hot. This method also prevents the plant foliage from getting wet, which makes your cucumbers less susceptible to powdery mildew.
You can also add a layer of organic mulch around the base of the plants. This will help retain moisture in the soil, and provide your cucumbers with a slow-release nutrient boost as the mulch breaks down.
Start fertilizing your cucumbers a week after the plants have started flowering, then repeat the application once every 3 weeks. A liquid, balanced fertilizer is ideal, with an N-P-K nutrient ratio of 10-10-10 or 20-20-20. Avoid nitrogen-rich fertilizers, as they promote abundant leaf and vine growth but fewer flowers and fruit.
Cucumbers benefit from regular pruning throughout the growing season. This will help the plants get bushy, and improve air circulation. Use a sharp pair of gardening scissors and trim the top of the cucumber plants when they are at least 2 feet tall (60 cm), or have at least 6 leaves.
Repeat the process once every couple of weeks as the plants mature, and remove any lateral suckers growing in between the flowering shoots. If you notice any wilted or damaged leaves, cut them as well, but take care not to trim any tendrils or flowers.
Most cucumber plants produce separate male and female flowers. In an open garden, especially one that’s visited by pollinators such as bees and butterflies, these insects will take care of pollination for you. But in a greenhouse, or in very humid and cold climates, you may need to help your cucumbers set fruit by manually pollinating them.
Start by identifying the two different types of flowers on the cucumber plant. Male flowers have short stems and usually bloom a couple of days before the female ones. The female flower has a small cucumber-shaped swelling on the stem.
To manually pollinate cucumbers, pick a day dry morning when the flowers are open wide. Snip the male flower off the vine and gently rub it against the female flower, to transfer the pollen. If pollination is successful, the small swelling on the female flower stem will start growing into a cucumber after a few days.
When to Harvest Cucumbers
You can start harvesting cucumbers 50 to 70 days after sowing. Check the information on the seed packet to see how long each variety takes to mature, and what size the fruit grows to. As a rule of thumb, it’s best to pick cucumbers sooner rather than later. If you leave them on the vine too long, they will develop a hard rind and start to taste bitter.
Always pick cucumbers that feel firm to the touch and have dark green, unblemished skin. Avoid picking cucumbers that feel soft, or are starting to turn yellow. Harvest regularly to ensure that the plant continues to produce more fruit.
Cucumbers are ideal for either fresh eating, pickling, or adding to sauces such as tzatziki. Slicing cucumbers can be kept in the crisper drawer of your fridge for up to a week. Cover them in a plastic wrap or an airtight container, to prevent them from shriveling up. Pickling cucumbers are ideal for — you guessed it — pickling, but if you peel the bumpy skin, they can make a tasty addition to salads.
Common Cucumber Pests and Diseases
Cucumbers can be susceptible to several pests which target both plants and ripening fruit. Some of the most common pests include aphids, cucumber beetles, squash bugs, and whiteflies. Check your plants regularly and pick the insects by hand, then spray the plants with an insecticidal soap solution. You can also plant dill, marigolds, and yarrow to attract beneficial insects, such as lacewings and ladybugs.
Common cucumber diseases include powdery mildew, Verticillium wilt, Alternaria leaf blight, and cucumber mosaic virus. Many of these plant diseases can be prevented by planting your cucumbers in full sun, providing air circulation, avoiding overhead watering, and growing resistant varieties. Of all the plant diseases to keep an eye out for, mosaic virus is the worst, as it has no cure. Remove infected plants immediately and burn them.
Companion Planting With Cucumbers
Some of the best companion plants for cucumbers are legumes such as beans, lentils, and peas. These crops fix nitrogen into the soil and give your cucumbers a nutrient boost during their growing stage. Cucumbers also grow well with root vegetables such as carrots and radishes and can provide them with shade during the hotter months of the year. Also, plants such as dill, nasturtiums, onions, and oregano will help repel pests.
Some gardeners recommend that you never grow cucumbers and tomatoes together. These two plants are susceptible to the same diseases, especially powdery mildew and mosaic virus. However, as long as you’re growing resistant varieties, ensure proper spacing to facilitate airflow, and practice crop rotation, growing cucumbers with tomatoes is completely fine.
How to Grow Cucumbers in Containers
Growing cucumbers in a pot is a great way to maximize your garden space and extend your growing season. This is an excellent method for small gardens, gardens with heavy clay soil, or for gardeners who live in an area with short summers.
Start with a large, five-gallon container or bucket, and fill it with a mix of compost and potting soil. Sow 2 – 3 seeds per container, about ½ an inch deep, and water them well. Keep the container in a warm, sunny location until the seeds germinate. Once outdoor temperatures reach at least 68°F (20°C), you can move the container to the garden. Water and fertilize your cucumbers regularly, and provide them with something to climb on.
Growing Cucumbers Indoors
Cucumbers can grow indoors, but there are a few essential details to keep in mind for a successful harvest.
- Always make sure that your cucumbers receive at least 6 hours of sunlight per day. If your home is too dark, it’s best to grow cucumbers under grow lights, especially in winter.
- For best results, try growing a dwarf or bush type cucumber such as Spacemaster, Fanfare, or Pick a Bushel. These varieties take up less space, and they don’t require trellises or supports.
- If you want to skip having to manually pollinate cucumbers, try growing parthenocarpic varieties such as Sweet Success, Diva, County Fair 83, or Picolino. However, keep in mind that these cucumbers love climbing, and will need a trellis for optimal growth.
No vegetable garden would be complete without the cucumber. A single plant can produce around 20 cucumbers, providing you with a great source of vitamins and minerals. Try growing a slicing cucumber variety for fresh eating, and a pickling variety to enjoy throughout winter. Remember to water and fertilize regularly, give the plants a hand with pollination, and you’ll never run out of tasty cucumbers in your home.