Ahh, for me April is a month of joy! While the air is warmer, the birds are singing, and flowers are blooming, I remain wary of planting warm season plants too early. In Virginia, most cold hardiness zones have a last frost date in April — the exception is an early May date for the mountain-based gardeners in zone 6a.
Find your plant hardiness zone and adjust your planting plans around it at Virginia Tech's state cooperative extension guide.
While at that site, check out which vegetables can be planted in April, per your hardiness zone. In zone 7a, cool season plants such as lettuce, peas, and broccoli to name a few, can be planted, but hold off until May to plant tomatoes, peppers, eggplant, and other warm season crops. I recently purchased a compost thermometer that can also be used to check the temperature of garden soil. Once the garden soil reaches 65-70°F at an 8” depth, those warm season nightshade plants will thrive.
April is always a race against the clock; not in a stressful way, but with the attitude and can-do spirit of a marathon gardener. Let’s start with the most important part of the garden: the soil. Spring is a good time to apply a ¼” of compost over the soil surface of any garden. This ¼" of compost is full of millions of microbes that invigorates soil life, adding nutrients for plant uptake. Note nutrients are most available to the plant when the soil pH is just below neutral 7. Check the pH and adjust according to the soil sample results to insure it rests in the range most plants prefer, that of 6.2-6.5. Acid-loving plants enjoy a pH of 4.5-5.5, a common pH in central Virginia but one unheard in the limestone-based soils in the valley. Following the soil test results, also incorporate nutrients as instructed using organic or slow-release fertilizers.
If any fertilizer falls on an impenetrable surface, take time to blow or sweep it back to the soil to avoid fertilizer-rich runoff during rain. Be water-wise by installing a rain sensor on the irrigation system to prevent irrigating during a rain event. Then, adjust your irrigation heads to greatly reduce water falling on hard surfaces. Working collectively yet individually is the best way to protect our waterways.
In containers and raised beds, add compost to bring the grade up. Gently blend it with the existing soil to prevent a layered effect that roots may find difficult to penetrate. After planting, apply a light layer of mulch until the seeds have germinated. As the plants grow, add more mulch to suppress weeds and retain soil moisture, keeping it no more than 3” deep. Remember to stagger seed sowing and transplanting to create a succession of blossoms or harvest over time rather than all at once. Water weekly all plantings, be they trees, shrubs, flowers, or vegetables in the absence of rainfall.
For plants that require staking, it's best to install the stakes during seed sowing or as they emerge from the ground. Waiting will not only damage the root system, but also the plant as leaves and stems are manually woven through the support structure.
Spring is a great time to de-thatch, aerate, and fertilize warm season grass lawns of Zoysiagrass and Bermudagrass. For cool season grasses, raise the mowing blades to 3-4” after sharpening them for the first cut of the season. Resist the urge to fertilize cool season grass in the spring. Doing so may promote abundant growth without the root mass to support it during warmer weather. Fertilize cool season fescue grass in the late summer to fall. As always follow the results of a soil test to prevent overfertilization; too much is not good for the plant nor for the aquatic life in our lakes and rivers.
I enjoy deadheading; meaning removing spent blossoms from plants like lilac, pansy, peony and irises, roses, too. While doing so, I take the time to look closely at each plant and marvel at the beauty while checking it out for insects and disease. I hand remove caterpillars or prune off an aphid-infested tip of new growth I spy. I pluck off the first black spot leaf, noting it’s time to begin the monthly application of a fungus-suppressing product. Remember, fungicides suppress the fungal spores, they do not eliminate them, so repeated applications are necessary per the product label.
In addition to deadheading spent blossoms, I prune spring blooming plants that have finished flowering for the season. Pruning out deadwood, crossing/rubbing wood, or randomly growing branches will promote the health of a plant without altering the natural growth habit. Opposite of spring blooming plants, which bloom on last year’s growth (aka old growth), summer blooming plants are pruned in the spring to promote new growth, which will produce an abundance of flowers later this season.
Happy Gardening!
- Peggy, Director of Park Operations and Horticulture at Maymont