April in the Vegetable Garden
Vegetable gardening really gets going in Central Virginia during April. The weather can still be pretty unpredictable though, so it pays to be “frost cautious.” Albemarle County and its surrounds are on the borders of the Piedmont and Mountain regions of Virginia. Extension Publication 426-331 puts Albemarle County in the Mountain region which has an average final frost date of May 10-15. On the other hand, USDA places Albemarle in Hardiness Zone 7a which specifies a final frost date of April 20-30. So planters beware, if you are motivated to plant warm weather crops early, be prepared to protect them if a surprise late freeze is our fate this year.
A separate-but-related guide to planting is soil temperature. Planting before soil reaches an appropriate temperature for your crops only delays germination or growth and really defeats the purpose of early planting. Investing in a soil thermometer is a wise move. On the other hand, warm soil is NOT an indicator of frost risk, so consider both variables in your planting decisions. A chart providing information on soil temperatures for optimum germination of vegetable seeds can be found in VCE Publication 426-316, titled “Seed for the Garden.”
Following is the April vegetable-planting schedule adapted from the VCE Publication 426-331. To identify transplants that can be planted outdoors this month, look for the vegetables marked with an asterisk.
|April 1-11||April 12-18|
|Lettuce, Bibb||Lettuce, leaf|
|Onions set)||Onions set)|
|April 19-25||April 26- May2|
|Beans, Bush||Beans, Bush|
|Beans, Pole||Beans, Pole|
|Beans, Wax||Beans, Wax|
|Lettuce, leaf||Onions set)|
|Squash, Summer||Squash, Summer|
|Squash, Winter||Squash, Winter|
|* Denotes Transplants|
|The suggested dates may vary for different areas.|
There’s still time. Tomato, eggplant, and peppers can still be started indoors from seeds.
April is the time to set out cool-weather crops such as broccoli, brussels sprouts, cabbage, cauliflower, lettuce and onions. But we have to wait until the danger of frost has passed to transplant tender plants such as tomatoes, peppers, and eggplant.
If you’re interested in starting an asparagus patch, April is planting time. Asparagus is a perennial that requires a permanent location, full sun and well drained soil with a pH close to 7.0. Plants can last 15 years or more, so careful location selection is important. Asparagus can be started from seeds or crowns. Crowns are a good idea since it takes a few years for the plants to reach peak harvest potential. For an excellent guide to starting asparagus, read Cleve Campbell’s article “Spear into Spring with Asparagus” in the March 2015 issue of The Garden Shed, https://piedmontmastergardeners.org/article/spear-into-spring-with-asparagus and Va. Cooperative Extension Publication No. 426-401, which specifies recommended cultivars for Virginia, Extension Publication 426-401.
Having trouble with plant markers fading when labeling with a “permanent” marker? Paint markers available from supply stores or Sharpies marked “paint” from craft stores, hold up well throughout the growing season.
Go vertical to save space in your garden. You can construct temporary or permanent woven wire “fences,” which will provide vertical support for runner varieties of beans, as well as for cucumbers. Plants can be trained to climb the fences, saving not only space, but also making harvesting easier. For additional information on vertical gardening, see “Intensive Gardening Using Trellises, Stakes and Cages,” https://www.pubs.ext.vt.edu/content/dam/pubs_ext_vt_edu/HORT/HORT-189/HORT-189-pdf.pdf.
When planning your crop arrangement, consider intercropping. Intercropping is growing two or more plants together for a variety of beneficial effects including weed suppression, balancing fertility impacts, reducing pests, thwarting disease and adding diversity. Find guidance on effective intercropping here.
One of the most important steps in planting comes before seedlings get near the garden. This is the process of hardening off, or gradually acclimating seedlings to outdoor conditions. These young plants have spent their short lives in a warm, protected place and won’t fare well if they are exposed too quickly to the elements. Start the hardening off process about 2 weeks before you intend to plant them outside. A few days before beginning hardening plants off, reduce the amount of water you give them, and cease fertilizing until they are planted in the garden. Put transplants outdoors in an area where they’ll be protected from the direct sunlight and wind. Leave them out for a few hours and bring them back inside. Repeat each day, gradually increasing the amount of time they are outside and the degree of exposure to sun and wind. After a week or so, leave them out overnight. If frost threatens, bring the seedlings indoors. Additional information on hardening off can be found at VCE Publication 426-001 titled “Plant Propagation From Seed.”
When transplanting seedlings in peat pots, gently tear off the top inch of the pot; the upper edges of the pot should be covered with garden soil to avoid wicking water away from the soil surface. Wicking may reduce the amount of moisture available to plant roots.
The best time to transplant is on a cool cloudy day or late in the afternoon to avoid the hot sun. The plants then have time to acclimate to their new environment. If the following day is hot and sunny, a row cover may be used to reduce stress on the plant. A row cover may also be used to help protect young transplants from a late frost.
Don’t be in too big a hurry to add mulch to the vegetable garden. Delay organic mulching to allow the soil to warm deeply, but mulch before weeds become established.
Save The Date! Join us at the Piedmont Master Gardener Annual Spring Plant Sale on May 4, 10-2:00 pm at the Tent at Stonefield in Charlottesville.
Adapted from “Monthly Horticulture Tip Sheets,” Albemarle County Extension Office website, Horticulture & Natural Resources, albemarle.ext.vt.edu/programs/horticulture-natural-resources