After Bulbs Bloom
Tidy up spring-flowering bulbs by snipping spent blooms of daffodils and hyacinth. Don't braid or clip leaves. Their photosynthetic efforts fuel next year's flowers.
Test Garden Tip: If ripening bulb foliage is an eyesore, consider planting bulbs behind partners whose leaves will hide unsightly bulbs. Choices include peonies, daylilies, coral bells, tall sedum hybrids, or perennial geranium.
For an instant spring show, fill containers with purchased forced spring bulbs from supermarkets and garden centers. Tuck in sweet alyssum for a ground-hugging, sweetly scented filler.
Dress spring pots with color, courtesy of flowers that love cool weather: pansy, viola, and snapdragon. Plant flowering stock for a spicy clove fragrance.
Last Average Frost Date
In northernmost regions and higher elevations, you can still plant cool-season crops. By seed, plant your radishes, peas, lettuces, and other greens; put in transplants of broccoli, cauliflower, and cabbage.
In warmer regions, the last average frost date is this month. Go ahead and plant seedlings of warm-season edibles (tomatoes, peppers, eggplants, basil) when all danger of frost has passed.
If you haven't already, get potatoes in the ground as soon as possible.
For Heat-Loving Plants
Wait to plant seeds of heat-loving crops like corn, green beans, squash, or cucumbers. Soil temperature needs to be 60 F for these seeds to germinate.
Test Garden Tip: Don't have a soil thermometer? 60F is warm enough to walk on comfortably barefoot.
Get the jump on weeds by applying a pre-emergent weed killer to beds and borders. Put it down in early April for best results. It works by preventing seeds from germinating, so don't apply anywhere you're planting seeds or hoping self-sowing annuals will appear
Clear out debris and muck from the bottom of the water garden and add it to your compost heap. Start feeding fish again when water temperatures hit 50 F or fish are active and eagerly eat food.
Finish tree and shrub pruning, but don't touch spring bloomers until flowers fade. You can prune evergreens until late summer. Don't prune later or new, tender growth will get zapped by winter cold
Start fertilizing roses
If you choose liquid fertilizers, apply every two weeks until August. For slow-release fertilizers, follow package directions, which may suggest adding to soil every 6 weeks. To use homegrown compost, add a spadeful to soil around roses every month.
Test Garden Tip: Some fertilizers include systemic pesticide. The benefit is that as you feed roses, you're also fighting pests. These products can kill beneficial insects and butterflies. Read the label to know the full impact on other insects.
Tackle mower maintenance if you didn't last month. Replace spark plugs, oil, and air filter. Sharpen the blade.
Test Garden Tip: In early spring, cold nights can make a shed-stored mower slow to start. Set it in the sun an hour or two before starting and let the sun warm the engine. Covering the engine with a black trash bag warms things up even quicker.
Bare patches & crabgrass
If you applied crabgrass preventer when forsythia bloomed, wait to seed bare patches until fall. Why? Crabgrass preventer keeps seeds from germinating -- including turf grass seeds. If you didn't apply crabgrass preventer, seed bare spots now for a lush summer lawn.
Early spring is a great time to spot spray or hand-dig dandelions. If spraying, choose a product that won't kill grass. If digging, wait until after a rain, when soil is soft.