Northern & Central Midwest
Pinch First-Year Strawberry Blossoms
Remove flowers of newly planted June-bearing strawberries as soon as they appear to allow the plants to put strength into developing roots. Remove flowers of everbearing and day-neutral strawberries until July 1. After that, allow them to flower and enjoy the fall crop.
Plant Warm Season Crops
Once the danger of frost is past and the soil is warm, it's time to plant warm-season crops such as peppers, eggplants, and tomatoes. Also, houseplants that will spend the summer outdoors can be taken outside then. Be sure to gradually acclimate or harden off any houseplants and seedlings raised indoors (this includes ones you purchase from a greenhouse) to outdoor conditions of temperature, sun, and wind before setting them outside for good.
Take Care of Your Peonies
Peonies will be getting ready to bloom soon. Fertilize them with a general garden fertilizer, and make sure you have support for the large blossoms so they don't droop after a rain. To produce larger blossoms, pinch off the smaller secondary flower buds as they form.
Nip Rose Problems in the Bud
Fertilize roses after their first flush of flowers. Deadhead hybrid tea roses as soon as the flowers fade, and constantly monitor the leaves for black spot. Remove any infected leaves and begin spraying with the Cornell baking soda formula (1 tablespoon horticultural oil plus 1 teaspoon liquid soap in a gallon of water).
Monitor Container Plants for Moisture
As the weather warms, be sure to monitor containers and hanging baskets daily. Remember that clay pots dry out more quickly than plastic. If the soil dries out enough to pull away from the sides of the pot, immerse the entire pot in a bucket of tepid water for half an hour and then let drain.