With spring coming, get plan to plant vegetables

Spring is just around the corner and it’s time to consider planting the garden. Most of us already know what we want to plant. But there are a number of items you should consider before selecting cultivars for direct seeding, growing your own transplants, or purchasing transplants from your local garden center.

The first consideration is the variety choice: either a proven variety for the area or an “All-American” cultivar that has been grown and tested across the United States. They are generally widely adapted and will provide a quality product.

The second consideration is disease tolerance and resistance, or how well the cultivar will stand up to disease pressure. Another consideration is the number of days it will take for the cultivar to produce its first crop.

For more detailed information on vegetable cultivars, see Nebraska Extension NebGuide G1896, “Selected Vegetable Cultivars for Nebraska.” This publication will provide an excellent starting point for cultivar selection.

Once you have selected the vegetables and respective cultivars to plant, planting the seed or transplants and getting them off to a good start will depend on environmental and cultural factors.  Soil moisture, planting depth, last expected frost date, soil fertility all play a part.  Soil temperature is one environmental factor that is often overlooked. 

Vegetables can be classified as cool or warm season. Hardy, cool-season vegetables include broccoli, cabbage, onions, lettuce, peas, radish, spinach, and turnips. Minimum soil temperatures to plant or transplant these vegetables are 38 to 45 degrees Fahrenheit, with daytime temperatures in the 40s.  These vegetables can withstand cooler nighttime temperatures.

Semi-hardy vegetables include beets, carrots, cauliflower, parsley, parsnips, and potatoes.  Minimum soil temperatures to plant or transplant these vegetables are 40 to 45 degrees, with daytime temperatures in the 50- to 60-degree range. These vegetables are less tolerant to cooler nights.

Tender, warm-season vegetables include beans, corn, cucumbers, spinach, and summer squash. Minimum soil temperatures to plant or transplant these vegetables are 55 to 60 degrees, with daytime temperatures above 55.  These vegetables do not tolerate cold or freezing temperatures.

Very tender vegetables include lima beans, cantaloupe, eggplant, pepper, pumpkin, winter squash, tomato, and watermelons. Minimum soil temperatures to plant or transplant these vegetables are 60 degrees, with daytime temperatures above 60.  These vegetables do not tolerate cool or cold temperatures.

A few other tips to consider: Planting seed or transplants too early may result in the death of the plant from freezing. The plants will not grow well under cooler conditions if planted too early.  They are more susceptible to disease and other environmental factors.

Set the transplants out during the daytime for 4 to 5 days to harden them off before transplanting.  Water the transplants before planting. Transplant on an overcast day or in the afternoon to reduce stress on the plant.

Plant the transplants far enough apart to avoid contact with each other.  This will reduce the chance of disease and insect transfer from plant-to-plant. Use foil or paper tubes inserted about an inch into the ground around the base and about 3 to 4 inches up the stem to help prevent cutworms from killing or damaging the plants. Avoid damage to the roots of the transplants.  Use wood shingles or other suitable material to provide protection from wind damage. Be sure to cover your plants if there is a chance of frost or freeze.

One last consideration: When planting super-sweet varieties of sweet corn, don’t plant different varieties side-by-side. Plant them in different parts of the garden as far away from each other as possible. The pollen from one variety on the other variety may cause the kernels on the ear to be tough.