Now is the Time for Thinning and Watering
If you planted cool weather vegetables, make sure these plants have enough space to grow. Crowded crops will not produce to their full size or cause root crops to warp or fork. Thin out out your plants. Follow spacing guidelines specific to each plant. It’s usually best to cut unwanted seedlings at the soil line, rather than pulling, to avoid disturbing plant roots.
Make sure to observe the VCE’s recommended planting dates and avoid planting before the average last killing frost dates in the Spring. Along the coast of Northern Virginia (Tidewater area), the average last killing frost date is between April 10 to April 21; more inland (Piedmont area) the average last killing frost date is between April 20 to April 30. Avoid common vegetable gardening mistakes caused by putting some plants in the ground too early. Continue to look at the recommended planting times that are mentions in March Vegetable Gardening.
Water is essential to plant health. It is recommended that vegetable plants receive at least an inch of water a week. Try to water early in the morning rather than the late afternoon or early evening. Morning watering helps to reduce the amount of water lost to evaporation, and gives a plant’s leaves a chance to dry. Plants are more susceptible to disease if their leaves are wet after dusk. Plants also do best when watered deeply and infrequently. By contrast, light, frequent watering encourages plants to develop shallow roots. Follow these recommended watering tips.
Mulching with organic compost and/or layering straw at the base of the plant will help to retain moisture in your soil and reduce evaporation. An inch of compost and/or bedding around your plants also helps keep weeds from growing. Straw (or the dried stalks of grain without the grain heads) is generally considered more suitable (and is less expensive) than hay for use as mulch and bedding in vegetable gardens.
If you are using seeds stored from previous growing seasons, you may want to test the germination of your seeds to see how well they will do when planted this year. Most seeds can last for years, if stored properly, but some seeds have a relatively short life and may no longer be viable. Learn how to test your stored seed for germination and about storing seed. Continue to harden-off tender transplants before planting outdoors.

Sweet potato slips refer to the shoots that can be encouraged to grow off a mature sweet potato. There are many online resources on how to sprout your own sweet potato slips indoors from available tubers. Here is an excellent video from the University of Maryland Home & Garden Center, as well as their complete article on sweet potatoes.
These recorded VCE/MGNV classes will be of special interest: