University of Vermont Extension 
Department of Plant and Soil Science

Summer News Article
Charlie Nardozzi, Senior Horticulturist
National Gardening Association, and
Dr. Leonard Perry, Extension Professor
University of Vermont
Moving spring-flowering bulbs, fertilizing vegetable plants, and pruning lilacs are some of the gardening tips for this month.

If you want to move some spring-blooming bulbs to another spot, wait until the foliage has turned yellow, then carefully dig them up and let them dry in a shady spot for a few days. Store the bulbs in a cool, dry place for the summer until it's time to plant them in fall.

Make a note of gaps in your spring bulb garden, and plan to plant bulbs there this fall. By choosing a variety of bulbs, from early-blooming snowdrops to late-blooming alliums, you can have a colorful show for months. Note the bloom times in plant descriptions. For example, Kaufmanniana tulips bloom early, while single, late tulips wrap up the spring show.

Cut back shrubby perennials, such as catmint and dianthus and veronica, when they finish blooming. This will tidy them up and encourage them to produce a second flush of flowers. If
your clematis blooms only in spring, once it's finished blooming you can prune damaged and wayward stems, and cut back stems if you need to control the size of the vine. Leave the decorative seed heads.

Tomatoes, squash, and cucumbers can use some nutrients now, so scratch some granular fertilizer into the soil around plants or in a shallow trench alongside a row. Do this when the soil is already moist, and then water it in.

There's evidence that fruiting of tomatoes and peppers is improved by applying Epsom salts, which contains sulfur and magnesium. Apply one tablespoon of granules around each transplant, or spray a solution of one tablespoon Epsom salts per gallon of water at transplanting, first flowering, and fruit set. You can find it at drug and grocery stores.

After lilacs finish flowering, prune off the old blossoms to increase the number of flowers next year. Do this soon because the plants will begin setting buds for next year's flowers. To reduce the height of the shrub, prune the old stems to the ground and allow new shoots to grow. Prune all at once, or gradually remove one-third of the old stems over a three-year period.

Check apple, cherry, and other fruit trees for nests of tent caterpillars. Blast low-lying nests with water to destroy them, or knock them to the ground and destroy them. A spray of Bt will kill emerging caterpillars but is not toxic to beneficial insects, birds, or humans.

Return to Perry's Perennial Pages, Articles