Even though tomatoes like it when it’s warm, most types of them have a hard time when the temperature hits the high 80s or 90s. These high temperatures can negatively impact tomato production just as much as cold temperatures.
Some bad things that can happen to crops when they get too much heat (and sunlight) are sun scald, fruit cracking, blossom drop, uneven ripening, and Yellow Shouldering Disorder. This is why it’s important to keep tomatoes cool during the hottest months of the year for better tomato production. Finding the best shade cloth for tomato plant protection is a big part of maintaining yield.
In this post we outline the best shade cloth for tomato production. We came to these conclusions after talking to a lot of different growers and looking at a lot of information from agricultural extension offices in a lot of different states.
Many things depend on the grower’s climate, which we’ll talk about more in this post. But for now, here are our findings from research we’ve done on the best shade cloth for growing tomatoes:
Even though reflective shade cloth can be useful, we chose the 40% black shade cloth as the best overall for production because it is a bit cheaper than the reflective options on the market.
If you have the money, you should definitely think about getting reflective shade cloth because it has extra benefits over aluminet and white shade cloth. We cover these in more detail further on in this post.
Our focus here is on high tunnel and greenhouse production. That is to say, we manufacture high tunnels and greenhouses. Even though we work closely with farmers and have grown plants ourselves, we find it best to look to experts and data to help us figure out the best ways to grow for yield and production.
Below are some quotes from agricultural extension services regarding the use of shade cloth for tomato production.
“Shade fabric (30-50%) will lower air temperatures within the high tunnel by as much as 5-8 degrees Fahrenheit”
“Yellow shouldering disorder (YSD) of tomatoes is exacerbated by high air temperatures. Shade cloth (30-50%) can reduce YSD.”
“The best shade level is 20 to 40% shade. even with our heat the whole plant doesnt need to be shaded. “.
My advice is to use shade cloth, but only the ones with a moderate shade level, like 30% shade or less. “.
“If shadecloth is used until the end of the season, crop yield might go up in a hot summer because fewer blossoms would fall off because of the cooler weather.” “.
– Wenjing Guan, Purdue State University Extension, Whether to Put Shade Cloth on High Tunnel Tomatoes
The research of agricultural extension offices, regardless of geographic location, has seemed to come to similar findings. More specifically, that shade percentages between 30% and 50% are best. These results appear to be true for many parts of the US where seasonal high temperatures and the number of days with full sun are different.
What we said at the beginning of this post is based on the different points of view from agricultural extensions across the country.
Even though the agricultural extension papers we looked at say that tomato production should use less shade cloth, we know that every climate is different and that shade cloth can be used in different ways to protect tomatoes.
Like, maybe your plan is to put up and take down shade cloth as the weather changes. It might make more sense to use a shade cloth with a higher percentage in this case to keep the temperature from rising too quickly on any given day.
Higher percentage shade cloth isn’t usually suggested by agricultural extension services for tomato growing, though. This is mostly because it could lower tomato yields.
According to Wenjing Guan at Purdue State University Agricultural Extension, plants grow bigger but thinner leaves, longer internodes, and less vegetative biomass when the shade level is higher than 5%. Water, nitrogen and potassium uptake was declined as shade density increase. “.
Further on in his report Guan states, “. 50% shade was put down when the greenhouse tomato started to ripen. After 3 weeks of shade, the total yield went down, but the early yield didn’t change. “.
It is important to note, though, that the study Guan is talking about above happened in the northeastern United States. Regardless of this fact, the decreased yield and nutrient uptake is enough to question higher shade cloth percentages.
If farmers in your area usually use a shade cloth percentage higher than 50%, there are probably good reasons for that. Or maybe the amount of time and type of application don’t stop the plant from growing, taking in nutrients, or producing. Following this link will lead you to some high-quality knitted 60% cotton shade cloth if this sounds like what you need to do.
White and aluminet shade cloth options are quickly becoming favorites for tomato producers. The reason for this is the additional heat they tend to keep off the structures. White or aluminet shade cloth doesn’t absorb as much heat as black shade cloth, which is why buildings covered in white or aluminet shade cloth can get even cooler.
Because aluminum and white shade cloths are reflective, they do a good job of cutting down on the light that comes in and sending the light that doesn’t come in back out of the tunnel.
This sounds obvious, but it needs to be stated. People who live in Cleveland, OH, where it clouds over 299 days a year, probably won’t need the same shade cloth as growers who live in Palisade, CO, where it doesn’t cloud over very often.
Extension services do a lot of good research and give great advice, but that doesn’t mean you can’t grow tomatoes with a different percentage of shade cloth. As mentioned above, some people put on and take off shade cloth intermittently. Even though this takes more work, some growers may want to do it if they have the time and energy to do so.
This might sound like checking to see how cloudy it is, but it’s really more about the time of day.
For instance, climates farther north or south of the equator may have days that are much longer during some times of the year than climates close to the equator. This can translate to a ton of sun.
I had a conversation about this with someone in Alaska, just the other day. Even though it gets very cold there, they get about 22 hours of daylight during some parts of the summer. That’s a lot of sun!.
In the scenario outlined above, the growers tomatoes are being grown inside a high tunnel. The tomatoes get a lot of heat during the longest days of the year because high tunnels are made to do that well. Combining that much sunlight with that much heat can make it hard to lower temperatures and keep tomato yields steady.
Tomatoes are one of the most profitable crops to grow inside high tunnels and hoop houses. As such, their yield and fruit quality should be a priority for growers.
Lessening of high temperatures will slow down blossom drop, which will mean that more fruits will be ready to be picked. Additionally, the reduction in intense sunlight will reduce the incidence of Sunscald and Yellow Shouldering Disorder.
Implementing some form of shade protection during the hottest months of the year is likely to significantly increase yields if you are growing tomatoes in a high tunnel. This includes shade cloth, 2040% shade cloth, and 2050% shade cloth.
Standard shade cloth can be used for about ten years. This means that it is an investment with a good “pay-back period” because higher yields could cover the cost of the shade cloth over time.
If you are a tomato grower who isn’t already using shade cloth, you might want to start looking into how you can use it to get more tomatoes and make more money.
Providing Sun Shade for Tomato Plants: Protecting Your Crop from Sunburn and Heat Stress
Tomatoes are warmth-loving plants that require at least 6 hours of direct sunlight per day for optimal growth and fruit production However, during periods of intense heat, too much sun exposure can actually damage tomato plants, leading to issues like sunscald, sunburn, and stunted growth. Using proper shading techniques allows you to shield your tomato crop while still providing enough light for vigorous plants and abundant harvests.
Why Tomato Plants Need Sun Shade
While sun is essential for tomatoes, excessively high temperatures can put plants under stress. Intense afternoon sun and heat cause more problems than morning rays. Issues like the following may occur:
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Sunscald – Light-colored damaged areas on fruit from sunburn, reducing quality
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Blossom drop – Extreme heat causes flowers to fall off without setting fruit
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Stunted growth – Plants stop growing when temperatures exceed 85°F
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Poor pollination – High heat impacts pollen viability and bee activity
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Nutrient deficiencies – Rapid growth and respiration deplete nutrients
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Sunburn – Leaves yellow, wrinkle and die back due to tissue damage
Even the most heat-tolerant varieties struggle when temperatures exceed 90°F for extended periods of time. Shading protects plants while still allowing sufficient light for photosynthesis.
How Much Sun Shade is Needed?
Tomatoes need some direct sun for fruit production, so complete shade will reduce yields. Light levels around 50-70% are ideal. Here are some guidelines:
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30% shade – Best for only very hot afternoons
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50% shade – Provides protection during intense heat
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70% shade – May limit yields except in extreme heat
Adjust shade levels based on your climate and tomato variety. Cherry types often do better with more shade than beefsteak. Monitor plant growth and fruiting to determine if more or less shade is needed.
Types of Sun Shade for Tomato Plants
There are various temporary and permanent shade solutions for protecting tomatoes in hot weather:
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Shade cloth – Breathable woven fabric that filters sunlight. Use 30-50% shade ratings.
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Row covers – Fabric “tunnels” that shade and protect from pests. Choose summer-weight material.
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Umbrellas – Open canopies that provide dappled shade and airflow.
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Arbors – Lattice or trellis structures that support vining plants. Use climbers like beans or cucumbers to provide living shade over tomatoes.
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Trees – Position tomato plants on the north side of trees or shrubs to take advantage of midday shade.
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Structures – Build simple A-frames covered with shade cloth or position planters on the shady side of sheds or fences.
Tips for Shading Tomato Plants
Follow these tips to successfully shade your tomato crop:
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Focus on afternoon shade when heat and sunlight are most intense.
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Allow for airflow so shade structures don’t create excess humidity.
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Use shade cloth or fabric covers that provide 30-50% shade levels.
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Monitor soil moisture and water frequently since shade reduces evaporation.
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Increase fertilizer by 25% to support growth in lower light conditions.
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Remove shade structures or lift row cover edges on cool, cloudy days to allow more light.
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Avoid complete shade which causes weak, leggy growth and lower fruit production.
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Start shading plants when temperatures exceed 85°F to prevent heat damage.
Selecting Shade-Tolerant Tomato Varieties
While all tomatoes need sun, some varieties are better adapted to partial shade conditions:
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Cherry tomatoes – Require less light and mature quickly. Try Black Cherry.
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Roma types – Compact growth habit and early harvest. Great for sauce.
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Small fruited – Produce even with limited light. Good choices are plum and grape tomatoes.
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Determinate – Grow as bushes and set all fruit at once. Shade won’t affect ongoing harvest as much.
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Early producers – Mature and ripen fruit quickly under stress. Yellow pear tomatoes are a good option.
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Disease resistant – Avoid problems exacerbated by shade like blight and mold. Try Celebrity or Park’s Whopper.
When sunlight is limited, prioritize early, compact varieties over late-season, heavy yielding types that require more light.
Balancing Sun Requirements and Afternoon Shade
Getting the right balance of sun and shade for robust tomato growth requires a little trial and error. Here are some strategies to try:
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Shade in the afternoon only when sunlight is most intense. Leave plants uncovered in the mornings.
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Alternate shaded and unshaded areas in your tomato patch. Monitor which plants do best.
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Gradually increase shade levels to find the maximum amount that still allows good fruit production.
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Remove shade structures during periods of cloudy weather to boost light levels.
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Utilize dappled shade from trees and shrubs rather than solid shade for a mix of sunlight.
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Reduce other stresses like watering issues, disease, and poor soil that are amplified by limited light.
With proper afternoon shading, vigilant monitoring, and choosing shade-adapted varieties, you can still grow tomatoes successfully even during hot summers. Pay close attention to your plants and make adjustments as needed to help your tomato crop thrive under cover.
A Garden Shade Cloth Plant Saving Guide (Tomatoes, Peppers, Cucumbers, & Fall Crop Examples)
FAQ
What is the best sun shade for tomato plants?
Is 70% shade cloth too much for tomatoes?
Is morning or afternoon sun better for tomatoes?
Do tomatoes grow in shade?
Technically, tomatoes are full sun plants not known to produce fruits in the shade. They require full sunlight for higher rates of photosynthesis to ensure the plant has enough energy to produce large fruits. The term shade-tolerant-tomato is a slight misnomer.
How do I choose the right shade for my tomato plants?
When choosing the right shade for your tomato plants, there are a few factors to consider: The amount of sun exposure your plants are getting. If your plants are getting full sun, you will need to provide them with more shade than if they are getting partial sun. The size of your plants. Larger plants need more shade than smaller plants.
What is a shade tolerant tomato?
Shade-tolerant tomatoes are those varieties that will still produce some fruit when not planted in the desired six hours of direct light per day. They may have smaller fruits to produce, as with cherry tomato varieties, or have shorter maturing periods that allow the plant to adapt better to lower light levels.
Can tomatoes grow in full sun?
Unless your garden is in total shade, you should have some luck with tomatoes. There are plenty of varieties that will tolerate a bit of shade, but all tomatoes will perform best in full sun. The adventurous gardener can try many unique and tasty tomatoes to find the varieties that work best in your particular garden conditions.
What is natural shade for tomato plants?
Natural shade is provided by trees, buildings, or other structures that block the sun’s rays. This type of shade is usually free, but it can be limited in availability. Trees are a good source of natural shade for tomato plants. They provide a large amount of shade, and they can also help to improve the soil quality.
Do tomato plants need a shade cloth?
By mid-season tomato plants have been in the ground for a couple of months and are pretty big. To protect plants properly from the sun, you need both a shade cloth and a way to support it. The support mechanism will need to reach up high enough to allow the cloth to cover the plant top to bottom.