Tips for April in Midwest Gardens BULBS When daffodils and hyacinth are finished flowering, clip off the faded blossoms. Allow leaves to naturally turn yellow; as they do so, they're storing food vital to next year's flower show. Bulb foliage turns yellow, then brown -- and can detract from a pretty spring garden. Disguise this ugly-duckling stage by planting perennials that will unfurl pretty foliage as bulb leaves die.
WEEDS Stop weeds before they start by adding a pre-emergent weed killer to plantings (there are organic and synthetic options available). You'll zap more weeds -- including early ones -- if you apply in early April. These types of weed killers prevent seeds from germinating. Do not use them if you count on self-sowers like larkspur, forget-me-not, cleome.
DIVIDE PERENNIALS Wait to divide spring-blooming perennials until after flowers fade. Wait to divide bearded iris until late summer. Get divisions in the ground by mid-September. Roots must be established before the ground freezes for clumps to survive winter.
Test Garden Tip: Divide peonies in fall, if at all. They don't require regular division, but can be dug if you want more or flower power has diminished.
Pruning Remember not to prune spring-flowering trees and shrubs until after blossoms fade. Make cuts immediately after blooming to lessen impact on next year's flower show. Prune evergreens from now until late summer. Stop pruning in late summer so that new growth can harden off before freezing temperatures arrive
Do not water your hostas until the threat of frost subsides. If watering is done early, the foliage pips may come up prematurely, and suffer from a late frost. (Late spring frosts seem to affect plantaginea and lancifolia the most.)
By keeping the foliage in the ground as long as possible, it’s also easier to clean up leaves and sticks without worrying about stepping on hosta pips coming up.
When the pips are still in the ground, it’s safe to apply 10-10-10 fertilizer without burning the hosta leaves