Field Notes — Stephen Albert, in the Sonoma Garden
Late July continues to offer excellent growing conditions for warm-season vegetables. Forecast highs in the upper 80s to low 90s are warm enough to keep summer crops growing vigorously without the prolonged extreme heat that can interrupt flowering and fruit production. Nights in the mid-50s allow plants to recover from the day’s heat while the soil remains warm enough to support rapid root growth and nutrient uptake.
If you’ve kept your garden watered through the long stretch of hot, dry weather, expect another productive week. Tomatoes should continue ripening steadily, peppers will begin sizing and coloring more quickly, cucumbers and squash should remain highly productive, beans will continue flowering and setting pods, and basil will produce another flush of tender leaves. Melons, eggplant, okra, and sweet potatoes also benefit from the consistently warm soil.
This remains one of the best weeks of summer for succession planting. With the five-day average soil temperature holding at 78°F, seeds of bush beans, cucumbers, summer squash, basil, and sweet corn germinate quickly and grow rapidly, giving you an opportunity to extend harvests well into late summer and early fall.
One number, however, deserves your full attention this week.
Although soil temperature remains nearly ideal, soil moisture has fallen to just 12% VWC. That’s well below the range where most vegetables perform their best. At this level, plants are no longer simply conserving moisture—they’re beginning to experience genuine drought stress. Even gardens that appear lush may have dry root zones where plants struggle to absorb enough water to support continued flowering and fruit production. (Track your soil temperature and soil moisture, and be sure to see the Heat & Soil Gauge below.)
The focus this week is clear: restore moisture before plants begin sacrificing production. Water deeply rather than frequently, maintain a generous mulch layer, harvest vegetables regularly, and schedule watering and garden chores during the cool morning hours. Gardens that receive consistent irrigation should continue producing abundant harvests despite the exceptionally dry soil.
Much of the United States will see afternoon temperatures climbing into the 90s°F this week, placing added stress on both gardeners and vegetable crops. When heat combines with warm soil and drying conditions, plants can slow their growth, drop blossoms, or produce smaller harvests unless they're managed carefully. The good news is that a few simple adjustments—watering deeply, mulching to keep roots cool, harvesting regularly, and providing temporary afternoon shade for sensitive crops—can help gardens continue producing through the hottest days of summer. If your garden is facing prolonged heat, be sure to explore my collection of posts on vegetable gardening in extreme heat, where you'll find practical strategies for protecting tomatoes, peppers, cucumbers, beans, leafy greens, and other summer vegetables until cooler weather returns.
The Complete Guide to Growing Vegetables in Extreme Heat
Practical strategies for protecting vegetables during hot weather, conserving moisture, and maintaining production.
Not every garden is on the same schedule. Use your soil temperature—not the calendar—to decide what to plant this week. Find the range below that matches your garden and choose crops suited to those conditions.
These temperatures are ideal for warm-season vegetables getting established. Plant tomatoes, peppers, eggplants, cucumbers, summer squash, pumpkins, winter squash, basil, sweet corn, pole beans, and bush beans. In regions with long growing seasons, you can also sow another round of carrots, beets, and lettuce in partial shade for a late-summer harvest.
Continue planting:
Bush beans
Pole beans
Cucumbers
Summer squash and zucchini
Sweet corn
Basil transplants
Warm-loving crops thrive in this range. Continue planting cucumbers, squash, pumpkins, melons, sweet corn, beans, okra, southern peas, basil, and heat-tolerant greens such as Malabar spinach and New Zealand spinach. It's also an excellent time to start planning and sowing the first cool-season crops where summer heat is beginning to ease.
These crops thrive in warm soil:
Bush beans
Pole beans
Cucumbers
Summer squash
Pumpkins
Melons
Southern peas (cowpeas)
Okra
Sweet potato slips
Only the most heat-loving vegetables germinate and grow well in very warm soil. Plant okra, southern peas (cowpeas), yardlong beans, sweet potatoes, Malabar spinach, New Zealand spinach, Armenian cucumbers, and many hot peppers. Delay sowing cool-season vegetables until soil temperatures begin to decline, or start them indoors for transplanting later.
Choose vegetables that love the heat:
Okra
Southern peas (cowpeas)
Sweet potatoes
Armenian cucumbers
Malabar spinach
New Zealand spinach
Heat-loving hot peppers (where the growing season is long)
Water planting beds thoroughly before sowing seed.
Pre-moisten the seed furrow so germinating seeds never dry out.
Keep seedbeds consistently moist until seedlings emerge.
Sow during the morning or evening to reduce evaporation.
Continue planting bush beans every two weeks for continuous harvests through late summer.
Don’t know your soil temperature? A simple soil thermometer is one of the best investments a vegetable gardener can make. It tells you when conditions are right for planting, often more accurately than the calendar, and helps you get better germination and stronger growth.
Feed the soil, not just the plants. Warm soils speed up the breakdown of organic matter. A light layer of compost beneath your mulch helps replace nutrients, feeds beneficial microbes, and improves the soil’s ability to hold water during hot weather.
The summer harvest continues at full speed. Harvesting frequently encourages vegetables to keep flowering and producing while preventing oversized fruit from slowing new growth.
Harvest as often as possible:
Zucchini
Cucumbers
Bush beans
Pole beans
Basil
Tomatoes
Peppers
Eggplant
Harvest during the cool morning hours whenever possible for the best flavor, highest quality, and longest storage life. Use pruners or scissors rather than pulling vegetables from the plant to avoid breaking stems or damaging vines.
While tomatoes, peppers, cucumbers, beans, and squash are at their peak, now is the perfect time to begin planning the next season. Many vegetables you’ll harvest this autumn and winter—including broccoli, cabbage, cauliflower, kale, carrots, beets, lettuce, spinach, and other cool-season crops—must be planted weeks before summer ends.
The best fall gardens aren’t planted after summer is over—they’re planned while summer harvests are still filling the kitchen. Spend a few minutes this week deciding what you’ll grow next, ordering seed if needed, and reviewing your planting schedule. When planting time arrives, you’ll be ready instead of scrambling.
Start here:
This week’s forecast is favorable for summer vegetables, but the soil tells a different story. After another week of hot weather and almost no meaningful rainfall, soil moisture has slipped to 12% VWC, creating conditions where roots struggle to keep pace with the water demands of actively growing plants. (Measure volumetric water content (VWC) by inserting a soil moisture sensor or probe into the root zone, where it estimates the percentage of soil volume occupied by water. For the most useful readings, measure at the depth where most vegetable roots are growing (typically 4 to 8 inches) and at the same time of day each time you check.)
Tomato and pepper plants continue carrying heavy crops while producing new flowers. Maintaining consistent soil moisture now will determine how well they finish the season.
Watch for:
Blossom-end rot
Blossom drop
Smaller fruit size
Cracked fruit after heavy watering
Sunscald
Afternoon wilting that persists into evening
At 12% soil moisture, avoid the temptation to soak extremely dry soil all at once. Water deeply and slowly so moisture penetrates into the root zone instead of running off the surface. Consistent irrigation over several days is far more effective than alternating between drought and flooding.
Remember that healthy-looking leaves don’t always mean healthy roots. The stress plants experience below ground today often shows up a week later as reduced flowering, slower growth, and lower yields. Protect the root zone now, and your tomatoes, peppers, cucumbers, squash, beans, and melons will continue rewarding you with abundant harvests well into August.
If your peppers and eggplants are growing lush green leaves but producing few or no flowers, heat is often the reason. When daytime temperatures stay above 90°F and nighttime temperatures remain above 75°F, these crops may delay flowering or drop blossoms to conserve energy.
Before adding fertilizer, take a close look at the plants. Too much nitrogen encourages leafy growth at the expense of flowers, so avoid high-nitrogen fertilizers until flowering resumes. Keep the soil evenly moist—not soggy—and apply a layer of mulch to keep root temperatures cooler and soil moisture more consistent.
A little patience often pays off. As temperatures moderate into the 80s and nights cool, peppers and eggplants typically begin flowering again and quickly set fruit. In the meantime, harvest any mature peppers regularly to encourage the plant to keep producing.
Garden Tip: If plants have been in the ground for six weeks or more and still aren’t flowering, switch to a fertilizer with less nitrogen and a little more phosphorus and potassium to support blooming and fruit development.
These numbers are for my Sonoma garden. Be sure to track the numbers in your garden.
Excellent for warm-season vegetables. Root growth, nutrient uptake, and soil microbial activity remain near their seasonal peak.
Critically dry. Immediate deep irrigation is essential to maintain healthy plants and continued fruit production.
89–92°F
54–56°F
The weather continues to favor summer vegetables, but the soil has become the limiting factor. Warm soil and comfortably cool nights create excellent growing conditions above ground, yet the root zone has become critically dry. Gardens receiving consistent deep irrigation and protected by a generous mulch layer should continue producing heavily. Gardens allowed to dry further are likely to see slower growth, fewer flowers, smaller fruit, and declining harvests.
Volumetric Water Content (VWC) measures how much water is stored in the root zone.
Most vegetables perform best when soil moisture remains between 25% and 35% VWC.
At 12%, nearly every vegetable in the garden is experiencing moisture stress, even if plants still appear healthy. Deep-rooted crops may continue producing for now, but shallow-rooted vegetables, container plants, newly transplanted crops, and recently seeded beds require close attention. As soil dries, plants divert energy away from producing flowers and fruit simply to survive.
This is also the point where inconsistent watering begins causing problems such as blossom-end rot on tomatoes and peppers, fruit cracking after heavy irrigation, bitter cucumbers, and reduced yields from beans and squash.
Read more at When to Water Your Garden: Understanding Soil Moisture and VWC Made Simple.
Think of soil temperature as the engine of your vegetable garden and soil moisture as the fuel.
This week, the engine is still running beautifully.
With soil temperature averagingd 78°F, warm-season vegetables continue growing rapidly. Roots absorb nutrients efficiently, beneficial soil organisms remain highly active, and newly planted seeds germinate quickly. These are nearly ideal soil conditions for tomatoes, peppers, cucumbers, squash, melons, beans, basil, eggplant, okra, and sweet potatoes.
The challenge is the fuel supply.
With soil moisture now down to 12% VWC, vegetables are using water much faster than many gardens are replacing it. Afternoon temperatures approaching 90°F increase transpiration, and each sunny day removes more moisture from an already depleted root zone.
The goal this week isn’t simply watering—it’s restoring and maintaining consistent moisture. Avoid allowing the soil to swing from extremely dry to saturated. Deep, steady irrigation encourages deeper roots, healthier plants, and more reliable harvests throughout August.
Think of this as your garden’s weekly report card. It shows at a glance whether conditions are ideal for growth, whether it’s time to pay closer attention, or whether hot weather and dry soil are beginning to place crops under stress.
🟢 70–80°F — Ideal
🟡 80–85°F — Watch irrigation carefully
🔴 Above 85°F — Root stress increases
🟢 25–35% — Ideal
🟡 20–25% — Drying
🔴 Below 20% — Water stress becoming likely
This week’s forecast hovers around the point where many vegetables begin responding to heat, especially when soil moisture is limited.
Tomatoes may reduce fruit set and produce smaller fruit.
Beans often flower less heavily.
Cucumbers may abort young fruit if moisture is inconsistent.
Lettuce bolts rapidly and becomes bitter.
Squash may drop blossoms during hot afternoons.
Basil grows quickly but begins flowering sooner.
Peppers sometimes pause before resuming fruit production.
Fortunately, nighttime temperatures in the mid-50s continue giving plants an excellent opportunity to recover before the next day’s heat. Keeping the root zone consistently moist will make those cool nights even more effective and help sustain harvests through the hottest part of the season.
Read more at The Complete Guide to Growing Vegetables in Extreme Heat.
This week's average soil temperature of 75°F is close to ideal for the bacteria and fungi that release nitrogen and other nutrients to vegetable roots. As soil moisture drops below 20% VWC, however, microbial activity slows and nutrients become harder for plants to absorb. Even if leaves still look healthy, roots are beginning to experience stress. A thorough watering followed by a fresh layer of mulch helps restore the soil environment that keeps vegetables growing.
Learn more about garden microbial acitivy: The Complete Guide to Regenerative Gardening and Farming
With soil moisture now measuring just 12% VWC, restoring water to the root zone is this week’s most important garden job. Water deeply and slowly so moisture penetrates 8 to 12 inches below the surface where vegetable roots are actively growing.
Water early in the morning whenever possible.
Irrigate slowly to prevent runoff.
Check soil moisture 6 to 8 inches below the surface before watering again.
Water containers once or twice daily as needed.
Inspect drip irrigation systems for clogged emitters, leaks, or broken lines.
Newly planted successions and transplants may need additional irrigation until established.
Remember that vegetables recover best from gradual, consistent watering—not from alternating between drought and flooding.
A fresh mulch layer is one of the most effective ways to conserve precious soil moisture during late July.
Maintain a 2- to 4-inch layer of:
Straw
Shredded leaves
Finished compost
Pine needles
Dried grass clippings (applied in thin layers)
Mulch reduces evaporation, keeps root temperatures more stable, suppresses weeds that compete for water, and feeds beneficial soil organisms as it gradually breaks down.
If mulch has thinned or decomposed during the summer, replenish it now before August heat arrives.
The vegetables you harvest this summer depend on tiny organisms you rarely see. Bacteria, fungi, and earthworms are busiest when soil temperatures are between about 60°F and 80°F. Keeping soil covered with mulch helps protect this living community from extreme heat.
Many warm-season vegetables produce more when harvested regularly.
This week:
Pick zucchini while young and tender.
Harvest cucumbers before they become oversized.
Continue harvesting beans every few days.
Gather basil often to delay flowering.
Pick tomatoes as they begin coloring indoors or on the vine.
Harvest peppers regularly to encourage continued fruit production.
Frequent harvesting keeps plants producing instead of directing energy toward mature seed.
Leave a few herbs such as basil, dill, cilantro, or fennel to flower. Their blooms provide nectar for bees and tiny beneficial wasps that help keep aphids, tomato hornworms, and caterpillars in check.
Don’t rely on the weather forecast to decide when to water.
High temperatures near 90°F may not seem extreme, but average soil temperature of 78°F continues pulling moisture from the root zone every day, and actively growing vegetables are using enormous amounts of water.
Likewise, don’t assume that plants which look healthy in the morning have enough moisture below ground. By the time leaves wilt severely or fruit begins developing problems like blossom-end rot, drought stress has often been building for several days.
Instead, let the soil temperature—not the air temperature—guide your irrigation schedule. Check moisture below the surface and water deeply before plants begin showing visible stress.
Late July is when successful gardens are managed from the roots up.
Air temperatures this week are favorable for tomatoes, peppers, beans, cucumbers, squash, melons, basil, and other summer vegetables. The challenge isn’t the weather—it’s maintaining enough moisture below ground to support the rapid growth taking place above it.
Gardeners who water deeply, preserve mulch, harvest regularly, and avoid allowing the root zone to become bone dry will continue harvesting heavily through August.
Protect the roots, and the harvest will take care of itself.
If the forecast holds, soil temperatures should remain in the upper 70s while daytime highs continue reaching the upper 80s to low 90s. These are excellent growing conditions for nearly every warm-season vegetable, and gardens with adequate irrigation should remain highly productive.
The one question heading into August is soil moisture. Unless your garden receives significant irrigation—or an unexpected summer rain—the root zone will continue drying. Maintaining a consistent supply of moisture will become increasingly important as tomatoes, peppers, squash, melons, cucumbers, and beans continue carrying heavy crops while producing new flowers.
Looking ahead, August is also the month when many gardeners begin sowing the first cool-season vegetables for fall harvest. Continue enjoying your summer harvests, but start making room in the garden and preparing beds for broccoli, cabbage, cauliflower, carrots, beets, lettuce, spinach, and other fall crops. The transition to the next gardening season is only a few weeks away.
Late July is the bridge between peak summer harvests and planning for the fall garden. These guides will help you manage drought stress now while preparing for the next season.
When to Water Your Garden: Understanding Soil Moisture and VWC Made Simple
Learn how to measure soil moisture, understand VWC, and know exactly when your vegetables need water.The Complete Guide to Growing Vegetables in Extreme Heat
Practical strategies for protecting vegetables during hot weather, conserving moisture, and maintaining production.Mulching Vegetables for Hot Weather
Discover which mulches best conserve soil moisture, moderate soil temperatures, and improve soil health during the hottest months.How to Water Tomatoes for Bigger Harvests
Learn the watering practices that prevent blossom-end rot, fruit cracking, and drought stress while producing healthier, more flavorful tomatoes.Succession Planting Vegetables for Continuous Harvests
Keep your garden producing by sowing new crops every few weeks throughout the growing season.The Complete Guide to Fall Vegetable Gardening
Begin planning now for cool-season vegetables that will carry your harvest well into autumn and winter.
Long-Stem Soil Moisture Meter: With soil moisture now measuring only 12% VWC, guessing is no longer good enough. A quality soil moisture meter lets you check moisture deep in the root zone before watering, helping you avoid both underwatering and overwatering.
Adjustable Watering Wand: A watering wand delivers a slow, gentle flow that soaks deeply without washing away soil or mulch. It’s especially useful for newly seeded beds, transplants, and containers while making deep watering around mature vegetables easier and more efficient.
Programmable Hose or Smart Irrigation Timer: Late July watering is most effective in the early morning. A programmable timer automates irrigation before sunrise, maintaining more consistent soil moisture while reducing evaporation and saving time.
Organic Mulch: Straw, shredded leaves, compost, or pine needles are among the best investments you can make during midsummer. A 2- to 4-inch layer reduces evaporation, keeps the root zone cooler, suppresses weeds, and gradually improves soil as it breaks down.
The weather forecast may suggest another typical summer week, but your soil tells a different story. With temperatures remaining nearly ideal and soil moisture at just 12%, the success of your garden now depends less on sunshine than on how well you protect the root zone. Deep watering, generous mulch, and regular harvesting will keep your vegetables thriving until it’s time to begin planting the fall garden. Happy gardening!
My books provide detailed guidance to support this weekly Blueprint, showing you exactly how to sow, transplant, and care for your garden each week.
The Vegetable Garden Grower’s Guide is a practical handbook for growing vegetables from planting to harvest. It covers soil preparation, planting times, crop care, and troubleshooting common problems—everything you need to grow a productive vegetable garden.
Vegetable Garden Almanac & Planner is designed to sit beside you through the gardening year. It helps you track planting dates, garden tasks, weather patterns, and harvests so you can learn from each season and improve the next.
Many gardeners like to use the two together: the Grower’s Guide for how to grow each crop, and the Almanac & Planner for keeping track of what’s happening in their own garden.
If you’d like to learn more, you can find both books here:
The Vegetable Garden Grower’s Guide
Vegetable Garden Almanac & Planner
For step-by-step guidance, visit the Harvest to Table YouTube Channel, where you’ll find more than 60 videos showing how to grow nearly every vegetable—from seed planting to harvest.
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