Most established trees and shrubs do not need to be fertilized, especially if you are already fertilizing an adjacent lawn area. In landscape and garden beds, an organic mulch layer will break down slowly over time and provide nutrients as well. It is better to underfertilize than overfertilize, so if in doubt, don't feed.
Don't Forget Some Hummingbird Plants
Hummingbirds like red flowers with a tubular shape, such as red salvia and pineapple sage, but they also like many other flowers, too. Treat them to perennials such as columbine, penstemon, heuchera, and hosta, along with native vines such as the honeysuckles (Lonicera sempervirens and L. heckrotti) and Campsis radicans.
New gardens often have the most weeds, mainly because turning the soil brings weed seeds to the surface where they germinate. A regular routine of hoeing with a swivel or stirrup hoe and hand weeding will help keep them from growing large. Using a layer of organic mulch can help prevent many of them from germinating in the first place.
Encourage Self-Sowing Biennials
Many old-fashioned spring-to-early-summer bloomers are biennials, such as sweet William (Dianthus barbatus), money plant (Lunaria), foxglove (Digitalis), and most hollyhocks. These plants bloom their second year and then die. Allow them to set seed and self sow in the garden each year so that you will have the next generation of plants coming along to bloom next year.
Prune Lilacs Now
After blooming, lilacs may be deadheaded (remove the faded flowers) and then, if needed, thinned to promote vigorous new growth. To thin this shrub, cut back some of the oldest stems near to the ground. Don't cut all of the stems straight across the top as this ruins the natural shape and structure of the plant.