Cucumbers grow best with long, hot, humid days with maximum sunshine and warm nights. Plants are extremely susceptible to frost.
Sow seeds outside only after danger of frost when soil has warmed. Make a second sowing 4 to 5 weeks later for a late summer or early fall harvest. Cucumbers are ready to harvest in 65 to 105 days, depending on the variety.
For an earlier harvest and to reduce the threat of insect damage to seedlings, start a few plants indoors in individual pots (or trays with separate compartments) about a month before your last spring frost date.
Select disease-resistant varieties.
Choose a fertile site with well-drained soil; yields suffer in soil that stays wet.
Set up trellises for plants to climb on. Trellised cukes are straighter and have fewer insect and disease problems.
To seed in rows, plant seeds 1 inch deep and about 6 inches apart.
To plant in hills, plant four or five seeds in 1-foot-diameter circles set 5 to 6 feet apart.
Thin cucumber plants in rows to 1 or 2 feet apart, depending on the variety, when 3 to 4 inches tail. Thin cucumber plants in hills to the healthiest two plants when plants have two or three leaves.
Keep soil evenly moist to prevent bitterness in cucumbers.
Side-dress cucumber plants about 4 weeks after planting, just as vines begin to run. Apply 2 handfuls of good compost or a tablespoon of 5-10-10 or similar fertilizer per plant in a narrow band along the vines of each plant.
Apply a thick layer of mulch about 4 weeks after planting.
See our article Summer's Bad Guys by Charlie Nardozzi for controls of common cucumber pests such cucumber, squash vine borers, and whiteflies.
Once cucumbers reach pickling or slicing size, harvest every couple of days to prevent cukes from getting overly large or yellow and to keep plants productive. Pickling varieties seem to go by their peak the fastest.