Blog by Kirsten Ann Conrad, Agriculture Natural Resource Extension Agent, Virginia Cooperative Extension, and FOUA Board Member
If you are tired of winter and hunger for spring, try planting peas as soon as the soil dries and the soil temperature reaches 40 degrees. Probably the most common variety is the shelling pea and the old standard in this group is Little Marvel. Though Little Marvel is still on our recommended list, we have a number of others that do well including Green Arrow, Knight, Maestro, Burpeeana and Mr. Big. All of these are early maturing types that allow us to harvest a crop before the hot weather arrives and stops production.
Snow peas are those commonly used in stir-fry that have a crisp edible pod. Recommended varieties include Dwarf Grey Sugar and Mammoth Melting Sugar.
Sugar snap peas resemble shelling peas but have a thick, fleshy pod and can be eaten fresh, steamed or cooked. Like snow peas, they are not shelled but eaten pod and all.
Other Recommended varieties for Virginia
‘Sugar Snow’ (tolerates downy mildew and wilt)
‘Wando’ (flat snow pea)
‘Dwarf Gray’ (sugar pea)
‘Green Arrow’ (English pea)
Peas should be planted shallow, about one-half inch deep, to encourage rapid germination and emergence. Seed can also be pre-soaked overnight for faster germination. Seed in the row should be spaced 2 inches apart. Many people often plant two rows 6 to 8 inches apart so the floppy plants can support one another. For some older varieties, this may not be enough. They may need trellising sticks, strings, or fencing to support the growing vines. Protection from rabbits and other wildlife may be necessary as well.
Vegetable Planting Guide and Recommended Planting Dates, Virginia Cooperative Extension
Vegetables Recommended for Virginia, Virginia Cooperative Extension
Peas, Cornell University
Green Peas, University of Maryland Home & Garden Information Center
Garden Peas, Clemson Cooperative Extension
How to Grow Peas, Michigan State University Extension
Plant Peas, Please, NC State Cooperative Extension
Though lettuce is sometimes planted as transplants, more often and most easily, it is planted directly from seed in late March to early April. Transplants do allow lettuce to mature earlier so that it escapes the excessive heat that can lead to a strong flavor and bitterness. But if grown in part shade or under shade cloth the season can be extended.
If using transplants, seed should be started four to five weeks before transplanting. Because transplants are planted at the same time as direct seeding, now would be a good time to begin. Use a seed starting mix and plant shallow as lettuce requires light for germination. A soil media temperature of 60 to 68 degrees will encourage germination but if it is too high, the seeds will not germinate. Also, a cooler temperature of 55 to 60 degrees should be used once the plants emerge.
Time to maturity varies depending on the type of lettuce. Head or crisp head lettuce is the slowest and is least likely to mature before becoming bitter. Shade cloth or growing under the shelter of a trellis of cucumber or peas will help with this problem. Leaf lettuce is the quickest, followed by bibb, romaine, and buttercrunch lettuce.
Leaf lettuce plants are spaced 4 to 6 inches apart, buttercrunch, bibb, and romaine are set at 6 to 8 inches and head lettuce should be at least 8 inches apart in the row. Lettuce does not have an extensive root system and requires regular watering if rainfall is lacking. We recommend a minimum for lettuce of 1″ per week with more frequent watering in fast drying soil.
Fertilize before planting according to soil test. Plants should also be sidedressed when about 1/3 grown. Sidedressing is done with fertilizers that have more nitrogen than phosphorus and potassium. Use 1/3 cup of nitrate of soda (16-0-0) or 1/4 cup of a 27-3-3, 29-5-4 or similar fertilizer per 10 feet of row. The latter fertilizers are lawn fertilizers but will work well for sidedressing as long as they do not contain weed killers or weed preventers. If you are in the habit of only using compost to boost fertility, be aware that after a winter of exposure to the air and weather, the N content of home compost is very limited.
Soil Temperature and Vegetables
Soil temperature is a much better measure of when to plant than air temperature or the calendar. Planting when soil is too cool can cause some seeds to rot and transplants to sit there. Unless you are experienced enough to know soil temperature by feel, you will want to use a soil thermometer.
A number of vegetables can germinate and grow at cool temperatures. For example, peas will germinate and grow well at a soil temperature of 40 F. Though lettuce, parsnips, and spinach can sprout at a soil temperature of 35 F, they prefer at least 45 F for best germination and growth. Radishes also do well at a soil temperature of 45 F. Even if the seeds of these cool-season crops are planted below the recommended soil temperature, the seed will rarely rot.
Warm-season crops such as tomatoes, sweet corn and beans prefer at least 55 F for germination (or transplanting), but others such as peppers, cucumbers, melons and sweet potatoes need it even warmer, about 60 F. Seeds planted too early, are likely to rot if planted when soils are too cool.
Thermometers with metal probes are sold in many garden, auto parts and hardware stores. Those in auto parts stores (used to measure the temperature inside air conditioning ducts) are often less expensive than those used for gardening. Take the temperature 2.5 inches deep at about 10 to 11 a.m. Temperature variations throughout the day and night affect soil temperature, with lowest readings after dawn and warmest around mid-afternoon. The late-morning reading gives a good average temperature. If taking the soil temperature at this time is not practical, take a reading before you leave for work and a second when you return home and use the average. Also be sure to get a consistent reading for four to five days in a row before planting, and make sure a cold snap is not predicted.
An excellent guide sheet on this subject is published by the Alabama Cooperative Extension System and is titled “Soil Temperature Conditions for Vegetable Seed Germination.” It can be found at https://tinyurl.com/1jw297zt
Sources: Ward Upham Kansas State University, Fairfax County Extension, Virginia Tech, and others listed above.
Kirsten Ann Conrad
Agriculture Natural Resource Extension Agent
Virginia Cooperative Extension
3308 S. Stafford St. Arlington, Virginia 22206
1108 Jefferson Street Alexandria, VA 22314
Master Gardeners of Northern Virginia: www.mgnv.org
Arlington Regional Master Naturalists: www.armn.org
Extension Master Gardener Help Desk: email@example.com
Extension Master Gardener Help Desk services are available 9-12 on weekday mornings. Contact: 703 228 6414 and firstname.lastname@example.org
Soil Test Kits are available in the Teaching Garden at the rear of the Fairlington Community Center and at Greenstreet Garden Center at Quaker Lane./Braddock St. as well as other locations listed at MGNV.org