University of Vermont Extension 
Department of Plant and Soil Science

Spring News Article

Charlie Nardozzi, Horticulturist and
Leonard Perry, UVM Extension Horticulturist
Staking peonies, dividing and relocating daffodils if needed, and fertilizing perennial tulips are some of the gardening activities for this month.   
Set up supports for peonies now while plants are just emerging, so their large flower heads don't bend to the ground next month. Circular flower rings with legs that stick into the soil are one option, but often the stems will bend where they droop and fall over the ring. Stakes encircled with twine around a plant is another option. The best support is afforded by wire mesh such as chicken wire with large holes (2-inch mesh is good). Spread it horizontally over the tops of the plants and attach it to some type of stakes at the sides. The flower stems and foliage will grow up through the mesh and hide it.
Daffodils and other spring-blooming bulbs need their foliage to replenish the bulbs for next year's flowers, yet sometimes you might want to relocate them after they flower but before the foliage yellows and dies. You can move them after blooming to a new spot, just keep the foliage, bulb, and roots intact. Keep watering and give them a dose of fertilizer. 
Many hybrid tulip bulbs propagate themselves by splitting into many smaller bulbs after blooming. The mother bulbs will usually not bloom again and the babies are too small to bloom yet, so these tulips are best treated as annuals. "Perennial" tulips -- Darwin tulips and Emperor tulips -- on the other hand, don't split so they will bloom for a number of years. Give them a dose of bulb fertilizer after blooming and cut off the flower stalks. Leave the foliage intact until it dies.
Ground covers such as vinca, ajuga, pachysandra, creeping foamflowers, lamium, and ivy can be divided and transplanted now to create new beds or enlarge existing ones. On a cloudy, cool day, use a sharp shovel or trowel to separate offshoots from mother plants and transplant them into a shady new location. Keep them well watered. 
If you're seeing red over those devastating red beetles on your lilies, it's time to get your squishing fingers loosened up. Lily leaf beetles often show up first in spring on leaves of the crown imperial (Fritillaria).  Check both sides of the leaves and down inside the center whorl of leaves. Also check the undersides of leaves for tiny orange eggs. The larvae have orange, brown, or greenish yellow bodies that are sometimes hidden under their excrement. The botanical insecticide  Neem is reported to kill the larvae and repel the adults. For best control, spray every 5 to 7 days after the eggs hatch. Some people also report success with spraying a lightweight dormant oil on the foliage to kill the eggs and larvae.
Clear grass and weeds from root zone areas around tree trunks, and remove any suckers growing from the base of the trees such as apples and crabapples. Spread compost, and top with 3 to 4 inches of bark mulch. Keep mulch an inch or two away from the trunks.  Remove any tree wraps or guards you placed on young trunks for winter protection.
If you’re planning to grow some warm-season crops like melons or sweet potatoes, don’t plant out until the ground has warmed to 65 to 70 degrees (F). Otherwise, plants won’t grow and may just rot.  Spread black plastic on the soil 2 to 3 weeks prior to planting to help warm the soil more quickly. You can start such crops in pots indoors in a sunny spot where warmer, a couple weeks before planting out, to get a jump on their season.

(Charlie Nardozzi is a nationally known horticulturist, author, gardening consultant, and garden coach; 

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