In the Vegetable Garden: July
With an early spring, plenty of sun and reasonably regular rain, our vegetable gardening season is off and running. Recent heat may have pushed cool weather greens to bolt a little early, but let’s view that as making way for succession planting with warm weather crops. The other side of the coin is that if you were an optimist and planted summer vegetables early based on the weather, you may well be picking all the cucumbers, tomatoes, squash and beans you can handle already.
In my own garden, slugs have been a bigger problem than in the past, probably due to the wetness of 2018. Slugs love moist environments and will eat any vegetation, but prefer the tender leaves of garden greens. Reducing moisture by thinning heavy mulches and thinning plants can help manage them. Sprinkling diatomaceous earth or crushed egg shells around plant bases can create a barrier to slugs reaching plant stems. Toads are a natural predator, so creating a toad house nearby may also help. Other deterrents include placing a pan of beer in the garden, inviting them to slither in and drown, or placing a partial melon rind upside down on the ground overnight, then collecting the rind and overstuffed slugs in the morning for disposal.
Tomatoes are the featured crop for many vegetable gardeners. There are a number of blights and diseases that affect plant and fruit health. A good rundown of different tomato disease and pest problems is contained in this article from the Cornell extension service. Guidelines for minimizing soil-borne disease issues include choosing resistant hybrids (next year), keeping plants up off the ground, mulching to prevent soil splash during rain and watering, watering only the base of the plant not leaves, removing the bottom 12” of leaves to reduce the risk of pathogen transfer from the soil, and watering early in the day so that plant surfaces are dry by nightfall. A number of diseases survive in diseased plant tissue, so good garden hygiene is important, as is crop rotation. Remove diseased leaves and branches and clean your cutting tool regularly. For more details refer to the June 2015 Garden Shed article Tomato Diseases.
Additional advice for vegetable gardeners in July includes:
- July is a good month to clean up space used for spring crops and do some sequential planting with warm weather plants, including beans, squash, cucumbers, sweet potatoes, eggplant, peppers, okra, and winter squash. Late July is a good time to direct seed cool season crops like broccoli, cabbage and Brussels sprouts. It’s smart to restore soil health and fertility by adding some compost to the top 4-6 inches prior to planting.
- Not sure of what varieties or cultivars of vegetables to plant? A comprehensive list of recommended vegetables for Virginia can be found in the Virginia Cooperative Extension Publication, “Vegetables Recommended for Virginia”.
- Watering becomes extra important in the hotter months, not only for overall plant health, but also for taste and texture of many vegetables. The garden typically needs about an inch of water per week. Early morning is the best time to water. Leaving leaves wet overnight increases susceptibility to fungal diseases. Mulching the garden is a good idea to stabilize ground moisture and help hold the weeds down.
- It’s important to control weeds around vegetables because weeds will out-compete vegetable plants for nutrients, water, and sunlight. The best method to control weeds is by mechanical extraction, meaning good old-fashioned weed-pulling or the use of a hoe. For small weeds, the “hoop” or “stirrup” hoe is highly recommended because it allows for shallow cultivation.
Another plus for the hoop hoe: it doesn’t bring weed seeds to the surface of the soil! Many weed seeds require sunlight to germinate. Deep cultivation or utilizing a tiller often brings seeds to the surface of the soil, facilitating germination of a new crop of unwanted weeds.
- To save space in your garden, construct temporary or permanent woven wire fences which will provide vertical support for runner varieties of beans, as well as for cucumbers. Plants can be trained to climb the fence, saving space and making harvesting easier since the vegetables will be hanging at a convenient height.
- A Threat to Basil is a fungal disease specific to sweet basil called fusarium wilt of basil. The fungus attacks the water-conducting tissue (xylem) within the stem. Infected plants will grow normally until they are six to twelve inches tall. Then the plants become stunted and will suddenly wilt. The stem may become curved, often referred to as a shepherd’s crook, and there will be brown streaks along the stems. Once established, the fungus can over-winter and survive many years in the form of spores, ready to cause new infections in basil or other members of the mint family that are planted in the same area. Currently, there is no fungicide approved for the treatment of this fungal disease, but it can be controlled somewhat by removing all diseased plants, by avoiding planting basil in the same location, and by planting disease-resistant varieties. Additional information on fusarium wilt of basil is available at ncsu.edu/-fusariumbasil
- Pepper plants are more productive if given appropriate moisture. Placing mulch (such as wood chips or leaf mulch) around plants will help retain soil moisture and reduce the need for frequent watering. In addition to conserving water, mulch provides the extra benefit of being a weed barrier.
- Okra blossoms are one of the showiest blooms in the vegetable garden, but they only last one day. Keep your eyes peeled if you don’t want to miss them. If the flower has been pollinated, a miniature okra pod can be seen beneath the wilted flower.
- Wondering if your blueberries are ripe enough to pick? Just try pulling a few berries from the stems. If they come off easily, they are ready to harvest. If not, they need to ripen more. Cover with netting or the birds will beat you to the fruit.
- Dry weather causes Swiss chard to bolt or prematurely go to seed. Water your plants to extend the season.
- Cucumbers develop a bitter taste if the soil is not kept consistently moist. Leaf mulch will help maintain soil moisture.
- Harvest cucumbers for pickling when they reach 2-4 inches in length; for table use, harvest when no longer than 5-6 inches. Remove any over-ripe cucumbers to encourage continuous production.
- Withhold water on potatoes when the plants begin to die down. Water and fertilizer may disturb the dormancy stage and cause regrowth, and may also cause potatoes to crack.
- If potatoes are visible along the soil surface, they probably look green. This coloration is caused by exposure to light. Green-skinned potatoes will taste bitter. Avoid this problem by covering potatoes with soil or mulch to protect them from the light.
- Pumpkin and squash blossoms are both beautiful and edible. To prepare squash or pumpkin blossoms for an appetizer, pick them after they open. Wash and drain the blossoms to remove insects and dirt, dip them in a flour or beer batter, and fry until golden.
- Although tomatoes are self-pollinating, they need movement to transfer pollen. If it is hot and calm for several days, gently shake plants to transfer pollen and assure fruit set. Hot temperatures can also interfere with blossom set.
- Shredded Chinese cabbage is a good hot weather substitute for lettuce in salads and sandwiches. A second crop may be started now for fall harvesting.
- In the summer, dry soil may become hard, making it difficult to work and inhibiting seed germination. Plant your succession and fall vegetables when the soil is moist, either after a rain or after watering the area thoroughly the day before you plant. Seeds may be planted in a shallow trench to conserve moisture.
- If caterpillars such as imported cabbage worm or cross-striped cabbage worms are overwhelming your cabbage, kale, collard or related cole crops, Bacillus Thuringiensis is an organic pesticide that can safely help control them. Follow package directions during application. For a deeper look at cabbage pests check Garden Shed article: OMG! What’s Eating the Broccoli?
- If you use any insecticides on vegetables, always check the label to understand how much time you need to wait before safely harvesting.
Thanks for stopping by The Garden Shed. We hope to see you again next month!
“ Vegetable Planting Guide and Recommended Planting Dates,” Virginia Cooperative Extension Publication No. 426-331, pubs.ext.vt.edu/426/426-331
“Weeds in the Home Vegetable Garden,” Virginia Cooperative Extension Publication No. 426-364, pubs.ext.vt.edu/426/426-364
“Basil Problem,” NC Cooperative Extension, https://growingsmallfarms.ces.ncsu.edu/growingsmallfarms-fusariumbasil/