How to Plant Cucumbers

If you have a vegetable garden or you're thinking of starting one, include a few cucumber plants (Cucumis sativus) to harvest crisp cucumbers for fresh-eating all season long. Many plants grow as climbing vines that are best grown with support, which also saves space in a small garden, but you can also choose a more upright, bush variety. Cucumbers grow as annuals in all parts of the United States and only need sun, good soil and abundant moisture to thrive.

Cucumber seeds need warm soil for good germination, with sprouting occurring fastest when soil is above 68 degrees Fahrenheit. If spring tends to be cool where you live, start cucumber seed indoors three or four weeks before you expect the arrival of warm temperatures. Sow seeds into moist potting soil or a soil-less mixture in flats or small pots, and keep the soil lightly moist. Once seedlings appear, keep them is a sunny window until you're ready to transplant them outdoors.

When the soil has warmed, you can direct-seed cucumber seeds into the garden or move your seedlings into their final location. Choose a spot with well-drained soil that gets full sun for most of the day. Add about 2 inches of compost or composted manure to your planting area to boost the soil's organic content and fertility, mixing the compost into the top few inches of soil before planting.

Plant seeds 1 inch deep, and space seeds 2 inches apart if you plant vining cucumbers in rows, then thin seedlings to every 8 inches once they appear. Space rows 5 feet apart. You can also plant in small hills, or mounds, with three to six seeds per hill; thin seedlings to two or three plants per hill. Space hills 3 to 5 feet apart. If you plant seedlings, set them 8 inches apart in rows or two or three seedlings per hill.

You can use the same spacing for bush varieties as for vining types, but if space is tight, set bush varieties an inch or two closer, either in rows or hills.

For vining cucumbers, using a trellis or fence helps conserve space while also keeping fruit off the ground where it might soften and rot; vines attach naturally to the strings or wires with curling tendrils. Trellising also helps produce straight cucumbers, improves air circulation to prevent fungal problems and makes it easier to find the fruits during harvest. Set up the support system before planting to avoid damaging plant roots. Vining types are available in many cultivars, including 'Straight Eight,' with 3-foot long vines, and 'Burpless Beauty,' with vines about 2 feet long.

Bush cucumber varieties grow naturally as upright plants and don't require support. But adding mulch under both bush and vining cucumbers helps prevent spoilage of any fruits that rest on the ground, while also conserving soil moisture. Use a sheet of black plastic, which can also warm the soil several degrees, or 2 or 3 inches of organic mulch such as straw.

Cucumbers do best when their soil is consistently moist, conditions that promote regular production of new fruits. Provide about 1 inch of water weekly, including rain. Adequate water is especially important during the young plants' first few weeks, but it's also needed throughout the season to prevent odd-shaped or poorly flavored fruits.

Cucumber plants can attract striped, yellow cucumber beetles, which spread a bacterial disease called wilt. This is best prevented early in the season by covering young plants with floating row covers at planting to prevent egg laying by beetles. Remove these when vines blossom to allow insect pollination, necessary for fruit production. Later in the season, control the beetles by hand-picking.

It's possible to extend the cucumber harvest into late summer or early fall by making successive plantings -- every two or three weeks -- until about three months before you expect the arrival of cold fall weather or a frost. Late in the summer or in early fall, about one month before your first fall frost, remove any new flowers by pinching them off with your fingers; this funnels remaining plant energy into existing fruits.