Planting Trees and Shrubs -- Plant container-grown trees, shrubs, perennial herbs, ground covers, and perennial flowers.
Planting Nursery Plants -- Plant warm-season annual flowers and vegetables (tomatoes, peppers, marigolds, petunias and the like) after all danger of frost has passed but in enough time for them to beat the summer heat. In hot desert areas, for example, that means no later than mid-February. If in doubt, give a quick call to the garden center nearest you. Microclimates and growing conditions can vary radically within just a few miles of each other and in places like Southern California, within just a few blocks of each other.
- Once the soil has warmed to 60 degrees F, plant seeds for corn, green beans, cucumbers, squashes, and other heat-lovers. You'll know the soil is warm enough once you can walk on it comfortably barefoot. Or wait until two weeks after your region's last average frost date.
Fertilizers -- Fertilize roses and fertilize perennials at the end of the month and keep them watered. You can use chemical fertilizers (follow package directions on amount and frequency) or organic fertilizers, such as compost, fish emulsion, and others.
- In the low desert and other hot areas, feed citrus, avocado, and deciduous trees now. In cooler coastal or higher zones, wait until next month.
- Late this month or early next, if desired, apply a pre-emergent weed killer to beds and borders. It will greatly reduce weeds later on. However, it works by preventing seeds from germinating, so don't apply anywhere you're planting seeds.
- Cut back woody and overgrown perennials. If in doubt, look at the base of the plant. If it is sending up fresh growth there, you can safely cut off the dead or old plant material now.
- Cut back old foliage from ornamental grasses, liriope (monkey grass) and mondo grass to just a few inches high. (Tip: If you or your neighbor have a power hedge clipper, it will make short work of tough-stalked ornamental grasses.)
- You can prune evergreens this month, but avoid pruning them later on this spring and summer.
- Keep up with the harvest of cool-season crops, such as peas, lettuces, and spinach. It will encourage more production. Continue to plant successions of these fast-growers for production over the next several weeks.
What To Plant -- Plant bare-root artichokes, rhubarb, and strawberries now.
- Clear out debris and muck from the bottom of the water garden, if you have one, and add it to your compost heap.
- Mulch your garden with 2-3 inches of mulch.
- Control snails with an organic or chemical bait.