Gardening in July

This month your time and efforts in the vegetable garden turn to harvesting and maintenance. It's a joy to pick fresh tomatoes, to eat them while still warm from the sun and gather the freshest cucumbers, summer squash, and your favorite herbs you've planted. Some of the earliest varieties will be producing at the beginning of the month, by late July most everything you planted in April and May will be producing, except for long maturing vegetables like winter squash and sweet potatoes that you'll harvest in early Fall.

It can also be a frustrating time for your garden, now is when all the 'critters' and diseases are attracted to the same bounty.

To preempt problems, check your garden as frequently as your schedule allows. A few times a week is ideal, or daily if possible. It doesn't mean spending hours each day but using the time as a review of conditions, then treating these regularly at each visit. My routine is to harvest first, being observant to finding issues while harvesting, then I turn my attention to treatment if I have time. Try to do this in the morning or early evening, so any treatment you apply is not done in the full sun or in heat of the day, but dries before the sun sets. Look for yellow, brown or wilted leaves, evidence of chewing, lack of fruit production, stunted growth and eaten produce.

Wilted leaves: yellowing, brown or wilting leaves on vegetables can indicate different issues depending on the plant. Browned leaves on tomatoes with brownish stems can indicate Fusarium Wilt or Verticillium wilt, these soil borne diseases pose additional challenges and will require a long-term response of crop rotation, soil solarization and in some cases replacement of soil in your raised bed.  Unfortunately, there are no effective fungicides, infected plants rarely recover, as they succumb to the disease the entire plant should be removed – I hold out as long as I can to let any fruit finish ripening before I pull the plant. (once all plants are removed try soil solarization to kill off the pathogens in the soil).

Tomato with early stages of Fusarium Wilt, which thrives in warm soils of 80°F, it often begins on one side of the plant with the browning of the leaf tips, eventually spreading throughout the entire plant.

Cucumber suffering from late stages of wilt

Wilted leaves can also indicate lack of moisture. Consistent deep watering is critical to the optimal growing conditions to prevent plant stress and increase natural resistance in these hot summer months. Whether you are hand watering or using a drip system on a timer, check the soil moisture when you are done. The soil should be moist to the deepest roots (tomatoes and eggplants can reach 12+ inches deep). If the soil is not damp beyond the top layer, then you are not watering enough. Water again, tracking the amount of time needed to ensure water has reached 5+ inches deep. Daily watering may be needed in extreme heat. Check the soil and water when the top 1” of soil is dry. To ensure you are not overwatering, the water should drain well, soil shouldn’t be soggy or have standing water.

Pepper plants yellowed and stunted due to lack of regular water.

Lack of fruit production: don’t have any tomatoes? It might be the temperature. Tomatoes prefer daytime temperatures of 70 to 80°F and nighttime temps above 60°F.  When days hit 85°F to 90°F and nights hover above 75°F, tomato flowers often fail to pollinate, then the blossoms drop off.

Winter and summer squash need pollinators, like bees, if you have a lot of flowers on your zucchini and cucumbers but no fruit, you may need to hand pollinate. See my post to help identify male and female flowers and step-by-step hand pollination instructions. Give your eggplant, tomatoes and peppers a slight shake to help self-pollinating blossoms.

Eaten leaves: There are many critters that eat leaves - small holes and rough edges may indicate cabbage worms, snails/slugs or grasshoppers. Lettuces and greens eaten down to the soil may be rats or squirrels. For worms spray with BT (Bacillus thuringiensis), for snails and slugs try Sluggo+ granules.  

Left to Right: 1) Slug or snail damage 2) leaf miners on cucumber leaves 3) lettuce eaten most likely by cabbage worms

Eaten Produce: Physical barriers will be the surest way to keep out birds, squirrels and rats. Building an enclosed structure around your garden bed is ideal but may not be feasible. If that is not an option, try protecting individual fruits with wire mesh made of window screen or reusing plastic clamshells. If you do build cages around your garden, use ½” hardware cloth – any larger holes the rats can squeeze through.

Tomato eaten by rats.

Tomato protected with a 'pocket' created with window screening mesh - cut, folded and secured with a house stapler.

July is typically too warm to start new plants by seed or transplants, so now through September implementing the routine of succession planting is more challenging. You can experiment with shade cloths to provide protection for new seedlings; this will require daily care and possibly watering several times a day until the plants are rooted deeply.

Use shade cloth to protect plants from burning on the hottest days. White covers shield strong light and keep out pests like the Cabbage White Butterfly; black covers offer more shade and can be purchased online in different percentages of shade. These are good for heat sensitive herbs and greens that can extend the season in these hotter months.

50% shade cloth protects basil, lettuce and kale from the intense summer heat.

NATIVE PLANTS

The wonderful thing about native plants is this time of year you really don’t have much to do. Some varieties will start to go dormant in the heat and have brown and yellowish leaves. Keep these intact for the plants to manage through the summer, then plan to trim back in the Fall. You can deadhead if you feel any old blooms are unsightly. I like to leave many to keep texture and form in the garden even after the birds have harvested all the seeds.

The tall stalks from spent blooms on the White Sage are graceful and add height to the garden, I don't remove these until later. Brownish leaves and finished blooms on Coyote Mint in the foreground balances nicely with the grasses and red blooms on California Fuchsia. At the far left, and behind the Sage, the soon-to-bloom bright yellow spikes on Western Goldenrod.

Watch closely any new plants that aren’t yet established and add supplemental water once a week if needed. Established natives from the previous year only need water once every week or two if you’d like to keep them actively growing through the summer.

Check your irrigation regularly for any leaks, and watch for plants that seem to be suffering, it may indicate a clogged dripper to repair.

While the midday heat will keep you inside, I encourage you to enjoy early mornings in your garden soon after the sun is up. I’m guilty of occasionally losing track of time with a cup of coffee and still in my pajamas! The cool mornings are my favorite time to be outside in July.