Northern & Central Midwest
Prune Spring-Blooming Shrubs After Flowering
Don't prune spring-blooming shrubs, such as honeysuckle, lilac, mockorange, spring-blooming spirea, flowering almond, forsythia, kerria, and weigela, until after they have finished their spring display. In late May or early June, you can prune for shaping or renewal before they set flower buds for next year.
Prune Summer-Blooming Shrubs Before Flowering
Now is the time, before buds begin to swell, to prune summer-blooming shrubs, such as hypericum, potentilla, rose, dogwood, summer-blooming spirea, beautyberry, butterfly bush, vitex, American cranberry, and barberry. They will set flower buds as they grow in the spring. Bring in the prunings to force into early bloom.
Clean Up the Garden
Enjoy those scattered warm days in March by cleaning up garden debris. Plan to spend only half an hour in the garden at a time and you will avoid being overwhelmed by garden cleanup. Be sure to dispose of debris responsibly, whether in your compost pile or your city or village compost.
Be Ready to Spray Dormant Oil
Keep a close eye on the weather and have your dormant oil ready for spraying. This environmentally sound practice will take care of a myriad of pests. Look for a non-windy day that is above 40 degrees F, with no chance of precipitation for 24 hours.
Monitor Soil Temperatures
Invest in a soil thermometer and watch for soil temperatures that are consistently in the 50s. This is when you can sow seeds of cool-season vegetables and flowers into the garden. Transplants of cool-season plants, such as broccoli and cabbage, can be acclimated and then planted in the garden.