If your garden gets full sun like mine, you know how intense it can feel in summer. Even though I live in a northern climate, I also garden in the high desert, which regularly hits 90°F or more in peak summer. All that southern exposure is amazing the other three seasons, but I quickly learned that shade cloth is necessary to get a good harvest in summer.
Once temperatures spike in July and August, many plants shut down and this shows up as stunted growth, tomato flowers shriveling up, poor pollination, or malformed fruit development.
Related: Common plant problems caused by excessive heat in summer
So if you’re a desert dweller or live somewhere with very hot summers, here’s what I’ve learned about protecting my plants from the heat, adding shade to a garden, finding the best materials to use, and different ways you can hang shade cloth to maximize your harvests.
But isn’t more sun better?
Generally, yes, more sun is always a good thing for vegetable gardens. Most crops need at least six hours of direct sun each day to be productive, so when I help people plan their gardens, I always tell them to find the sunniest spot in their yard.
After all, you can always create shade if you need to, but you can’t bring in more sun.
When the sun is blazing between midday and late afternoon, many plants start to struggle. Leafy greens bolt prematurely, peppers get sunscald, and tomatoes stop setting fruit. Heat-stressed plants become more vulnerable to pests. Hot weather combined with inconsistent watering also leads to other problems like blossom end rot, catfaced tomatoes, and cracked tomatoes.
You can avoid these issues by hanging shade cloth over your garden to protect plants at both ends of the season. The key is to shade your plants before you really need to, if you want the best possible outcome.
Shade cloth should go up in late spring to keep salad greens from bolting, remain through mid-summer to help prevent blossom drop, and protect new transplants and seedlings in late summer when you start transitioning your garden to cool-weather crops.
Read more: How to plant a fall garden when it’s still hot outside
Disclosure: If you shop from my article or make a purchase through one of my links, I may receive commissions on some of the products I recommend.
How to add shade to a hot garden
You’ll need three things:
- A support structure
- Shade cloth (between 30 percent and 50 percent)
- A way to attach the shade cloth to your structure
Types of support structures
My setup is simple: I use the same low tunnels that hold my frost cloth in winter.
A low tunnel (also called a mini hoop house) is a permanent or temporary frame that supports different types of covers. It’s typically made with 1/2-inch EMT (electrical metallic tubing) conduit, 1/2-inch PVC pipes, heavy-gauge wire, or plastic-coated steel hoops.
But low tunnels aren’t the only way you can hang shade cloth. Heavy-duty stakes, steel T-posts, 4×4 posts, bamboo poles, and steel poles all make good supports, and you can even combine them with an existing structure (for example, if you want your shade cloth to span an area between your poles and the side of your house).
For temporary structures, you can usually get away with pushing or pounding the poles into the soil several inches deep. Permanent structures will require digging post holes and setting the posts with concrete for stability.
What to buy
Types of shade cloth
Shade cloth is typically labeled with a percentage that indicates how much sunlight the fabric blocks, ranging from 30 percent to 90 percent. A 30 percent shade cloth, for example, blocks 30 percent of the sun’s rays while allowing the remaining 70 percent to pass through. The higher the percentage, the denser the weave and the more shade it provides.
Further reading: All the different types of row covers, explained
Here’s a general rule of thumb for choosing the right shade cloth percentage:
- Northern regions (north of the 40th parallel): I recommend 30 percent shade cloth. This provides enough protection from the sun while still allowing enough light for your plants to grow. It’s also best for fruiting crops like tomatoes, peppers, and cucumbers, which love sun but can’t take too much heat.
- Southern regions (south of the 40th parallel): Opt for 50 percent shade cloth. The denser weave prevents sun scorch and helps keep plants cooler during heat waves. This higher percentage is also ideal for protecting leafy greens like lettuce and spinach and extending their season.
Or, you can split the difference and use 40 percent shade cloth, which is versatile enough for a variety of plants (including mixed vegetable gardens).
What to buy
Does the color of shade cloth matter?
Technically, yes. Black shade cloth absorbs some heat during the day and releases it at night. This keeps temperatures a bit more stable in climates that cool off significantly once the sun sets.
White shade cloth reflects sunlight and heat, thus reducing heat buildup under your support structure. If your summers consistently exceed 100°F, white creates a cooler environment for your plants.
That said, it’s okay to use black shade cloth in a hot climate if it’s easier to find. Just make sure you suspend the cloth a couple feet above your tallest plants to allow ample airflow. (You don’t want the shade cloth to drape directly on your plants and trap all that heat against them.)
Can you use bed sheets, burlap, or other materials for shade?
Sure. In a pinch, any lightweight material you have around the house will work to shade your plants, including bed sheets, burlap, linen tablecloths, rolls of mesh, and even the same frost cloth you use in winter.
(The trick with using frost cloth is to just make a canopy with it, and not drape it over the sides of your structure.)
I’ve also seen people use patio umbrellas and nylon tarps over their garden beds. Since all of these materials differ in how much light they let through, pay extra attention to your plants each week. If they look like they’re getting leggy or stretching toward the sides where there’s sun, or the soil stays wet for longer, your plants may be getting too much shade.
How to hang shade cloth
You can use spring clamps, snap-on clamps, shade cloth clips, or carabiners to attach shade cloth to your support structure. These are easy to add and remove, especially if you need to raise the shade as your plants grow taller.
Zip ties, twine, rope, and bungee cords also work, but aren’t as quick or adjustable as a simple clip.
In my experience, heavy-duty plastic clamps are a better option than metal because they’re less likely to rust in the elements. Mine live outside year-round—under rain, snow, and high-desert sun—and I usually replace a few of them every three to four years, which is a pretty good run for plastic clamps.
What to buy
Ideas for holding up shade cloth in a garden
In my own garden, I attach shade cloth to my low tunnels using heavy-duty spring clamps.
Depending on what I need to cover, I use either an 8-foot-wide shade cloth that covers the entire bed, or a 5-foot-wide cloth that gives midday shade and leaves the sides of the bed partially open. (I also have a couple other widths to fit wider or narrower beds, but the 8-foot and 5-foot widths work well for a standard 4-foot-wide bed.)
This raised bed also uses EMT conduit for its low tunnel, but opts for a more permanent attachment method with zip ties threaded through grommets:
The same floating row cover and heavy-gauge wire you use to protect cabbage seedlings from pests can also be used to shade sensitive new transplants:
PVC pipes connect to make a rectangular low tunnel that protects a small garden bed:
A similar support structure can be built into a raised bed to suspend different types of covers over crops throughout the season:
Drape smaller pieces of shade cloth over individual tomato cages to shield against intense midday and afternoon sun:
To shade a new shrub or tree, you can build an “X” frame like this out of bamboo poles, PVC pipes, or EMT conduit to hang your shade cloth:
These gardens use wooden stakes of all sizes to suspend shade cloth over plants:
A sturdier and taller steel frame can be used to erect shade over a larger area:
If you have downed branches, upcycle them into rudimentary posts to make your shade structure:
The side of your house (or shed or fence) can be used as an attachment point to create shade over a garden bed:
Steel posts like these offer a more permanent solution to shade your garden area (and in the off season, you can hang string lights from them):
