While you're spreading decorative mulch, check to see that the mulch isn't getting too deep, especially around trees. A 2- to 4-inch layer is plenty. More than that and you might inhibit oxygen and water movement in the soil. If necessary, just remove some of the old mulch and compost it. Keep mulch several inches away from stems and trunks to minimize disease problems.
Extend the Bulb Display
Make a note of gaps in your spring bulb garden, and plan to plant bulbs there this fall. By choosing a variety of bulbs, from early-blooming snowdrops to late-blooming alliums, you can have a colorful show for months. Note the bloom times in plant descriptions. For example, Kaufmanniana tulips bloom early, while single, late tulips wrap up the spring show.
Be Patient with Perennials
Some perennials are up and growing strong now, while others may not have emerged yet. Before you give up on a plant, wait a few more weeks for signs of life. Hostas are especially slow to emerge. Take extra care when weeding and cleaning up beds so you don't damage the crowns and young shoots.
Remember Foliage Plants
There are some exciting new, and not-so-new, annual foliage plants available. Varieties with dark foliage combine well with light-colored flowers, as well as bold reds and chartreuse. Those with silvery foliage look great with jewel-tone flowers. Plant fuzzy-leaved varieties where you can reach to caress them and enjoy their irresistible texture. Coleus foliage is so colorful it can stand on its own.
Harden Off Transplants
Even if you're planting after your average last frost date, you still need to harden off indoor-grown seedlings before setting them into the garden. Skipping or rushing this process can result in chill damage and sunburn on tender growth. Acclimate plants to outdoor conditions over the course of at least a week, and preferably two, by gradually increasing the amount of time you leave them outdoors.