Take Advantage of Discounted Perennials
You can get some great deals on perennials now, and even if you don't have a spot ready for them in the flower border, plant them in the empty spaces in the vegetable garden when you pull out broccoli and other early crops. You can transplant them into their permanent locations in the fall or spring.
Keep Tomatoes Evenly Watered
Dark leathery spots on the blossom end of tomatoes is likely to be a condition called blossom end rot that's caused by uneven watering. Mulch will help moderate the fluctuating moisture levels that nature provides, and it's not too late to spread some around your plants.
Propagate Oriental Poppies
Most poppies resent transplanting, so a good way to propagate Oriental poppies is by root cuttings. Once the plants have dried up, dig up pieces of root and cut them into smaller pieces. Plant these sections, and sprouts will form this summer. By next year, you'll have new flowering plants.
Blueberries benefit from an acidic fertilizer each year. Apply 1/2 pound of ammonium sulfate when the bushes start blooming, and another 1/2 pound four to six weeks later, right about now. If the leaves turn yellow with green veins, they may have an iron deficiency. Applying 2 to 3 ounces of ferrous sulfate or iron chelate around the base of the plants will help correct this.
Fertilize Container Plantings
Frequent rains leach fertilizer from the soil of container plantings, so they need to be fertilized more often than plants in the ground. Mix liquid fertilizer into the watering can and use it weekly. Don't fertilize when the soil is very dry or it can burn the roots, so you may need to water plants first, then water with the fertilizer solution.