How to Grow Cucumbers

Is there anything more refreshing than a crisp, cool cucumber on a hot summer day? Cucumber (Cucumis sativus) is a warm-weather annual vegetable that's easy to grow. As long as you provide your plants with consistent water and warmth, they will reward you with plenty of fruit. They grow prolifically and need room to climb, but they can be trained to grow in almost any space.

Types and Habits of Cucumbers

There are two basic types of cucumbers and two different growing habits. The growing habits are vining and bush, while the types are pickling and slicing. The choice of growing habit is often determined by the size of your garden. Cucumbers can have either a vining or bush growth habit.

• Vining cucumbers require support such as a trellis or fence to grow properly.
• Bush cucumber varieties are more compact and better suited for containers or small gardens, though they may still need some support. They grow quickly and are perfect for succession planting.

Both pickling and slicing types can grow on either bush or vining plants. Although there are just two basic types of cucumbers, there are many options within these types.

• Pickling cucumbers are smaller, stouter, and have more spines with drier flesh, which allows them to soak up more brine—making them perfect for pickling.
• Slicing cucumbers are larger, longer, and have thinner skins that are not bitter, making them ideal for salads and fresh eating.
• Bonus: Seedless cucumbers, often marketed as "burpless," are a type of slicing cucumber that produces sweeter fruit with thinner skin than other slicing varieties.

Best Cucumber Varieties

When choosing cucumber varieties, consider both the types and growing habits. For a pickling type that will grow in a pot, look for a bush pickling cucumber. If you have ample space and want fresh cucumbers for salads, opt for a vining slicer.

Like most vegetables, cucumbers come in heirloom and hybrid varieties. Heirloom cucumbers often have less-developed disease resistance and are not as prolific as modern hybrids, but they usually offer better flavor, color, or other unique characteristics.

Popular Cucumber Cultivars

• Early yields: ‘Sassy’ or ‘Calypso’
• Pickling: Boston Pickling and Parisian Pickling (great for making gherkins)
• Seedless: Burpless and Burpless Bush
• Heirloom/specialty: Lemon Cucumber

How to Plant Cucumbers

You can plant cucumbers from seed or transplants. Growing from seed is both easy and cheaper.

When to Plant Cucumbers

These warm-weather plants should be seeded directly into the garden or transplanted outside no earlier than two weeks after the last frost date. The soil must be 70 degrees Fahrenheit for the seeds to germinate. Don't be tempted to plant too early; cucumbers are vulnerable to cold damage. Ensure the danger of frost has passed before planting. If you live in a colder climate, help warm the soil by covering the hill or row with black plastic for a few days before planting.

Sowing Indoors

To get a head start, sow cucumber seeds indoors about three weeks before transplanting them outside. They germinate easily, especially with bottom heat. Use a heat mat or place the seeds on top of the refrigerator for warmth to help them develop strong roots.

Preparing a Planting Site

Cucumbers need full sun (at least six to 10 hours each day) and warmth to thrive. They prefer fertile, well-drained soil with a neutral or slightly alkaline pH and plenty of organic matter.

Make sure the soil is moist but not soggy, as cucumber vines don't like wet, compacted soil, which can lead to root rot. If your soil isn't fertile, improve it before planting by mixing in compost or aged manure. Work the organic matter into the soil 6" to 8" deep for the best results.

Planting Techniques

The exact planting depth and spacing depend on the variety. Refer to the seed packet or plant tag for details. In general, plant two to three seeds at least 1 inch deep and 12" to 3' apart in a row.

Consider the size of the trellis the vines will climb on. Using a trellis usually allows you to reduce spacing to 1' to 2' apart. When seedlings reach 4 inches in height, thin them to one-and-a-half feet apart. Apply fertilizer at planting, one week after blooming, and then every three weeks, directly to the soil around the plants.

Another popular planting method is in mounds or hills. Space the mounds 1' to 2' apart, planting two to three seeds in each mound. Thin to one plant per mound once they reach about 4 inches in height. Cover freshly planted cucumber seeds with netting or row covers to prevent pests from digging them up. Once the seeds have germinated, mulch with compost to help keep pests, diseases, and weeds away, and to keep the soil moist.

Companion Plants

Like many vegetables that need pollination, cucumbers benefit from being grown near plants that attract pollinators. They also grow well with some other vegetable plants. Here are some plants to grow alongside cucumbers:

• Dill attracts pollinators and predatory wasps that kill insect pests. It's also a good kitchen pairing for both slicing and pickling cucumbers.
• Nasturtiums and marigolds may help repel pests that feed on cucumbers, such as cucumber beetles.
• As nitrogen-fixing legumes, peas and beans help enhance soil fertility, making them good companions for almost any vegetable, including cucumbers.
• Tall sunflowers can be used as a living trellis for cucumbers. Plant a few cucumber seeds around a sunflower seed in a mound, and let the cucumber vine grow up the sunflower stalk.
• Lettuce can be grown as a living mulch under a cucumber trellis in the summer. The cucumber plant will provide shade for heat-sensitive lettuce.

How to Grow Cucumbers

Cucumbers are easy to grow. Learn how to grow cucumbers from seedlings, starting with cups placed on a windowsill. Learn when to transplant your cucumber plants to the garden and how to prepare your garden soil for cucumbers. Laurie March also shows you how to care for your cucumber plants by treating them for powdery mildew and when to harvest cucumbers for pickling.

Growing Cucumbers

Trellising

Trellising is a preferred method for growing cucumbers. Both vining and bush habits need support. Training vines to climb saves space and protects the fruit from damage by keeping it off the moist ground. Without support, cucumbers will spread all over your garden. Training them to grow on a trellis or tomato cage helps keep the vines in check and your fruit clean. Set up the trellises and start training the vines early to avoid damaging the plant.

Watering

Consistent watering is crucial for growing cucumbers. They need at least 1 inch of water per week (more if it's hot). Inconsistent watering can lead to bitter-tasting fruit.

Water slowly in the morning or early afternoon at the base of the plant to keep the foliage dry, as wet foliage can encourage leaf diseases. If possible, use a soaker hose or drip irrigation for the best results. Water frequently when seedlings emerge and increase watering once the plant sets fruit. During this phase, side-dress your plants with compost or well-rotted manure.

Fertilizing

Apply fertilizer at planting, one week after bloom, and every three weeks, directly to the soil around the plants.

Common Pests, Diseases, and Problems

Though cucumbers are generally easy to grow, there are a few pests, diseases, and problems to watch out for.

No or Little Fruit

If cucumber plants aren't setting fruit, it's likely a pollination issue. Cucumber plants produce both female and male flowers. Male flowers appear first, followed by female flowers that grow at the base. For fruit to set, both must bloom simultaneously. This might not happen early in the plant's life, so give it time. If pollinators are lacking due to weather or insecticides, hand-pollinate by using a paintbrush to transfer pollen from the male flower to the center of the female flower.

Pests

Throughout the growing season, watch for pests that love cucumber plants. Cucumber beetles, squash bugs, and aphids can quickly ruin your harvest. Inspect plants often. If you spot any pests, treat the plant with a natural organic pesticide to control the outbreak.

Disease

Powdery mildew is a common disease for cucumber plants, developing when leaves get wet. It looks like a white powdery substance on the leaves. It starts with a few spots but can spread quickly.

The best way to prevent powdery mildew is to keep the leaves dry by watering at the base of the plant and keeping weeds down to promote proper airflow. If you notice any signs of mildew, apply fungicides at the first sign to prevent further spread.

Harvesting and Storing Cucumbers

When to Pick Cucumbers

Don't let cucumbers get too large before harvesting, as they will taste bitter and have tough skins and hard seeds. During peak harvest time, pick cucumbers every few days. Regular harvesting encourages the plant to keep setting fruit.

• Generally, harvest slicing cucumbers when they are 6" to 8" long.
• Harvest pickling cucumbers when they are around 2-3" long.

A good quality cucumber will be uniform in color, firm, and crisp. Use a clean, sharp knife or pruners to cut the stem above the fruit. Do not pull the fruit, as this can damage the vine.