University of Vermont Extension 
Department of Plant and Soil Science

Summer News Article

Charlie Nardozzi, Senior Horticulturist
National Gardening Association
Mulching, pest control, and proper harvest are some of the tips for this season’s vegetable garden.

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.

Reduce the weeds in walkways in your garden by covering the soil with some type of mulch. Some people like to use carpet scraps placed upside-down. Several sheets of moistened newspaper topped with hay or straw works very well, especially if you move your planting areas around a bit from year to year. Landscape fabric topped with wood chips or gravel is a good choice if the walkways are permanent. Try to avoid the habit of tilling to remove weeds because the process brings up weed seeds from deeper in the soil and exposes them to the light they need to grow.

Indeterminate tomato plants, such as 'Better Boy', will produce many suckers. A sucker is a new shoot that starts where a branch connects with the main trunk. Removing suckers will decrease the number of fruits produced, but the remaining tomatoes will be larger and will ripen sooner.

Set your tomato supports in place before plants get too large. Smaller determinate (bushy) varieties can be supported with small cages, but larger indeterminate (vining) varieties need large cages or tall stakes. Secure cages with stakes so they don't topple.

Blossom end rot shows up as dark sunken spots on the blossom, or non-stem, end of tomatoes, peppers, and squash. It's caused by a calcium imbalance in the plant.  The soil may have adequate calcium, but the plant isn't able to take up enough to supply the rapidly developing fruit. To minimize the problem, keep soil evenly moist, apply a layer of mulch to conserve moisture, don't over-fertilize (especially avoid high-nitrogen fertilizer), and avoid damaging plant roots while cultivating.

Coffee grounds, diatomaceous earth, and even sharp gravel can deter slugs and snails. Spread any of these materials in a ring around individual plants. Wrap pots with copper tape to keep slugs from crawling up. Inspect foliage and squish or pick off any insects that have already passed the barriers.

Young cucumber, melon, and squash plants are easy prey for cucumber beetles. As the seedlings grow, these yellow-striped or spotted beetles emerge to feed on their foliage. The beetles also spread bacterial wilt disease. To control them in a small planting, suck them up with a portable vacuum cleaner or spray beneficial nematodes on the soil.

It's not too late to sow lettuce, beets, carrots, radishes, and other short-season crops for a late-summer harvest. Shade lettuce, if possible, during late afternoon to keep young plants cooler, or grow them next to larger plants that provide some shade. You'll need to water more often on these hot days than you did in spring and early summer. Mulch between rows to preserve moisture and block weed growth.

Harvest tomatoes, zucchini, beans, and other fruiting crops frequently to encourage continued production. Remove any fruits that have gone by unless you're in competition for the biggest zucchini! You don't want the plant to produce mature seeds because that will signal that it's time to slow down fruit production.

Herbs are best harvested just as they are beginning to flower. That's when they have the highest concentration of essential oils -- and flavor -- in their leaves. Harvest entire branches back to within a few inches of the main stem to encourage new, bushy growth.

Begin harvesting onions when about half to three quarters of the leaves have died back. Then gently dig or pull the onions and store them in a dry, shady place with good ventilation, such as an outdoor shed or barn, for 10 days to two weeks. After the onions have cured, put them in slatted crates or mesh bags and store them over winter indoors in a cellar with low humidity and temperatures between 33 and 45 degrees F.

When the daytime temperatures no longer rise above 65 degrees F in late summer and early fall, it's time to pick the green tomatoes. Wrap them individually in newspaper and let them ripen indoors, or try some fried.  

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