The chief task of Southern gardeners is fighting drought. Northern gardeners should be watchful for dry conditions, too, but not to the same degree. Mid-summer is a good time for Northerners and Southerners alike to take stock of the garden and consider suitable adjustments for next year's garden.
- Continue to remove suckers from tomato plants and to check that they are supported either with stakes or tomato cages.
- Infestations of insects to be on guard against include but are not limited to those of thrips, tomato fruitworm, tomato hornworm, spider mites, chinch bugs, scale, snails, and slugs. Also look out for diseases such as leaf spot, powdery mildew, and rust.
- Inspect plants for Japanese beetles (Popillia japonica), including gourds, pumpkins, and squash.
- Fertilize heat-resistant flowers such as coleus, hibiscus, Melampodium, Pentas, plumbago, moss rose, and zinnias.
- (Mid-July:) Pinch mums one last time. Pinching later in the summer would reduce the blooms that you are counting on for fall displays.
- Pick what's ripe regularly to improve yields. Zucchini plants, for example, will keep bearing through summer as long as you keep ripe fruits picked.
- Pick blueberries before the wild birds eat them. To avoid having to be so vigilant, practice sound bird control. The most common way gardeners have of protecting blueberries from birds is by covering them with nets.
- Inspect fruit trees for water sprouts and prune them off. They will steal energy from fruiting branches.
There will likely be extended heat waves in July in the Mid-Atlantic. Keep your plants adequately watered to avoid losing your investment of time, energy, and money in them.
- Inspect plants for damage from pests such as groundhogs and rabbits and, should you find any, take quick action: They can rob you of your harvest in no time. Consider growing rabbit-proof and groundhog-proof plants next year.
- Pick up annuals that garden centers put on sale. You can revitalize them during July and August and have them ready for autumn flower beds and container gardens.
- Check that your automatic irrigation system is functioning properly. If it's clogged up anywhere, it could spell trouble for plants.
There will be scorching days in July in the Midwest and even extended heat waves. Stay ahead on the watering to avoid losing any plants.
- To prevent them from wasting energy on producing seed, deadhead your spring bulbs after they are done blooming. Also, fertilize them. But wait till the leaves have yellowed before trimming them off.
- (Late July:) Sow peas for a fall crop.
- Check your automatic irrigation system: It needs to be functioning properly during the peak of the summer heat.
The Northeast sees its hottest weather in July. Save beach trips for the worst days, but water before you leave. This month also calls for stepping back and taking stock of what is in bloom, with an eye to adding to that floral color in future years.
- The abundance of shrubs and perennials in bloom in spring is just a memory now. You have plants such as garden phlox getting ready to flower now, and, soon the flowers of rose of Sharon will furnish your yard with interest. But look for other options to inject color into your yard. Become a student of sequence of bloom.
- Check garden centers for annuals such as sweet alyssum that have been put on sale. They may not look like much now, but you can bring them back to health with some TLC and use them in fall plantings.
- Harvest vegetables and berries regularly.
- (Late July:) Sow peas for a fall crop.
If ever you are glad to be gardening in the Pacific Northwest, it is in July. The average high is 76 F and the average low 57 F. This makes it one of the most moderate climates in the country. Out of all 12 months, you will enjoy the lowest humidity and the most sun this month.
- Continue deadheading annual flowers to promote more blooming.
- Deadhead dahlias.
- Divide irises (Iris germanica).
July is sunny and dry in Northern California. The average high in San Francisco, for example, is 67 degrees F, the average low 54; you will get virtually no rain, and another factor working to dry out the soil in July is the wind. Southern California is predictably warmer, with an average high of 83 degrees F and an average low of 64 degrees F.
In Northern California:
- Sow the seeds of heat-loving vegetables such as tomatoes, peppers, okra, eggplant, and cucumbers.
- Fertilize cane berries such as raspberries.
- Spray grapevines to avoid getting mildew on foliage.
In Southern California:
- Plan your fall garden.
- Keep irrigation systems in tip-top shape. You do not want them to fail at this critical time.
- You can still plant citrus trees and tropical fruits.
In the high desert, July is hot. In Santa Fe, New Mexico, for example, expect an average high of 86 degrees F and an average low of 54 degrees F; you will get about 10 days of rain. If Santa Fe is hot, then Phoenix, Arizona, is blistering, as summer is peaking. You will have an average high of 106 degrees F, an average low 83 degrees F, and hardly any rain.
- This is when you most need your automatic irrigation system to be in top working order. Inspect it to see that it is, and effect any needed repairs and/or adjustments.
- Mulch wherever possible to conserve moisture.
- To prevent sunburn on young perennials and succulents, furnish them with some shade. This is easiest to do when you are growing them in containers (so that you can move the containers around as needed).
It is quite hot in July in the Southeast. Atlanta, for example, has an average high of 89 degrees F and an average low of 71; this city will get 12 rainy days in July.
- Watch for fungal disease, which is promoted by so much rain. When you find instances of fungal diseases such as powdery mildew, apply a fungicide to get rid of it. Note which parts of the garden are affected, and, next year, make it a point to provide more spacing between the plants there (increased airflow cuts down on fungal disease).
- Ensure that your automatic irrigation system working properly.
- Succession sow the seeds of sunflowers. By planting some every two to three weeks, you will end up with a steady supply of sunflower seeds.
- Start planning the fall vegetable garden.