Cucumber is a tender, warm-season vegetable that produces well when given proper care and protection. The vines of standard varieties grow rapidly and require substantial space. Vertical training methods and new dwarf varieties now allow cucumbers to be grown for slicing, salads and pickling, even in small garden plots.
When to Plant
Cucumbers are usually started by planting seeds directly in the garden. Plant after the danger of frost has passed, and the soil has warmed in the spring. Warm soil is necessary for germination of seeds and proper growth of plants. With ample soil moisture, cucumbers thrive in warm summer weather. A second planting for fall harvest may be made in mid- to late summer.
Cucumbers may be transplanted for extra-early yields. Sow two or three seeds in peat pots, peat pellets or other containers 3 to 4 weeks before the frost-free date. Thin to one plant per container. Plant transplants 1 to 2 feet apart in rows 5 to 6 feet apart when they have two to four true leaves. Do not allow transplants to get too large in containers or they will not transplant well. Like other vine crops, cucumbers do not transplant successfully when pulled as bare-root plants.
Spacing & Depth
Plant seeds 1/2 to 1 inch deep and thin the seedlings to one plant every 12 inches in the row or to three plants every 36 inches in the hill system. If you use transplants, plant them carefully in warm soil 12 inches apart in the row.
Cucumber plants have shallow roots and require ample soil moisture at all stages of growth. When fruit begins setting and maturing, adequate moisture becomes especially critical. For best yields, incorporate compost or well-rotted manure before planting. Cucumbers respond to mulching with soil-warming plastic in early spring or organic materials in summer. Use of black plastic mulch warms the soil in the early season and can give significantly earlier yields, especially if combined with floating row covers.
Side-dress with nitrogen fertilizer when the plants begin to vine. Cucumber beetles should be controlled from the time that the young seedlings emerge from the soil.
In small gardens, the vines may be trained on a trellis or fence. When the long, burpless varieties are supported, the cucumbers hang free and develop straight fruits. Winds whipping the plants can make vertical training impractical. Wire cages also can be used for supporting the plants. Do not handle, harvest or work with the plants when they are wet.
Pick cucumbers at any stage of development before the seeds become hard. Cucumbers usually are eaten when immature. The best size depends upon the use and variety. They may be picked when they are no more than 2 inches long for pickles, 4 to 6 inches long for dills and 6 to 8 inches long for slicing varieties. A cucumber is of highest quality when it is uniformly green, firm and crisp. The large, burpless cucumbers should be 1 to 1 1/2 inches in diameter and up to 10 inches long. Some varieties can grow considerably larger. Do not allow cucumbers to turn yellow. Remove from the vine any missed fruits nearing ripeness so that the young fruits continue to develop. The cucumber fruit grows rapidly to harvest size and should be picked at least every other day.