University of Vermont Extension 
Department of Plant and Soil Science

Spring News Article
Charlie Nardozzi, Senior Horticulturist
National Gardening Association, and
Dr. Leonard Perry, Extension Professor
University of Vermont
Hardening off seedlings, planting container gardens, and clearing around tree trunks are some of the gardening tips for this month.

Be sure to harden off indoor-grown seedlings before setting them into the garden. Skipping or rushing this process can result in chill damage to tender growth. Acclimate plants to outdoor conditions over the course of at least a week, and preferably two, by gradually increasing the amount of time you leave them outdoors.

To get a head-start on the season, plant container gardens and keep them indoors until danger of frost has passed. To reduce watering, incorporate water-absorbing crystals into the potting mix when you plant. It's hard to add them afterwards. Since clay pots dry out faster than plastic, use plastic pots set inside clay pots to help hold in moisture.
Grouping pots together also will help reduce moisture loss.

When planting containers of annual flowers, keep in mind that many of the newer varieties you find in pots in garden stores will need more fertilizer than older varieties.  Unless you can apply liquid fertilizer to them weekly, or according to label directions throughout the season, consider using a slow release fertilizer.  These are pellets you add at planting, and that release nutrients throughout the season.  You can find these at most garden stores, along with label recommendations on how much to add.

After all the rain we've had, the soil is saturated and compacted. Avoid stepping in garden beds and tilling or digging until the soil dries out a bit. But you'll want to attack those weeds that have been exploding with new growth. Use a long-handled weeder or a kneeling pad to reach them without stepping close to plants. Once the soil dries, cultivate the surface lightly to break any crust.

With spring rains and snowmelt, nutrients may need to be replenished in your garden soil and in containers. Dilute a liquid fertilizer and spray the foliage, then water the soil with the solution. Always fertilizer when the soil is already moist or the nutrients can damage roots.

Clear grass and weeds from root zone areas around tree trunks, and remove any suckers growing from the base of the trees. Spread compost, and top with a couple of inches of bark mulch. Keep the mulch an inch or two away from the trunks. Leave existing mulch to decompose and add nutrients back to the soil.

Sow new crops of beets, carrots, and summer lettuce to extend the harvest. You don't need much space, you can sow a border around other vegetables. If possible, choose a spot
that's partially shaded by taller plants for sowing lettuce, so it will stay cooler.

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