Wait to prune lilacs or viburnums until after they are done blooming. Don’t wait too long after blooming. They will start setting buds during the summer. Best time to prune them is within two to three weeks after the bloom.
Don’t prune evergreens just yet. You will be cutting off new growth. Best time to prune evergreens is late March or early April. Light pruning can be done around July 4th.
If you haven’t already, blow leaves and other debris out of the plant beds. Fluff the hardwood mulch lightly. A mulch depth of 3 inches is ideal. Top-dress the mulch if necessary. Pull mulch back from the bases of trees to prevent mold and decay.
Your lawn has just started growing. You will have a stronger, healthier lawn if it is allowed green up on its own. You can fertilize at the end of May .Do not rake or de-thatch. You will shred the still-tender growth. De-thatching is a chore usually done in the fall.
Aerating can be beneficial in either season spring or fall. Fall is generally considered the best time for lawns here in Minnesota. When combined with overseeding, it helps the turf through winter and prepares the lawn for a green spring. Aeration is spring is a good idea in high traffic areas of your lawn, for compacted soils, or heavy clay soils.
One note: Do not aerate during the first year your lawn is sodded or newly-seeded.
Be careful about planting summer annuals such as begonias, dianthus, coleus, celosia, impatiens, petunias, etc. until after Mother’s Day. Climatologically speaking, we can still get frost in the 3rd week of May. Remember, the temperature does not have to be below freezing. A calm night with clear skies and temperatures in the mid-30s would do it.