Shade Cloth

We’ve had a few inquires about our shade cloth, so I’m going to share what we have here and how we’re using it. I don’t consider myself a shade cloth expert. We’ve used it for a couple of seasons here. I can speak to the benefits we’ve seen.

For one - during the hottest summer weather, just about all of the plants we grow would prefer to be under shade cloth. As a rule, most plants perform best when they are at temperatures close to where we feel comfortable. Many would love to be between 65F and 85F all the time.

But temperatures in high tunnels and on landscape fabric can soar on hot, sunny days. If you’re not sure how warm your spaces get, I advise you to stick a thermometer or remote reporting sensor in your growing areas and have a look at what your plants are feeling. Our unheated farmer’s friend tunnels can reach 130F on sunny days, even when the doors and sides are open. That is too hot for more plants. The heat can lead stressed plants to bolt and bloom short or produce small flowers.

Farmer’s Friend (note: their web store is closed on Saturdays)

We use 50% shade cloth on some tunnels to prevent extreme heat. I remove it for stretches of cloudy days or cooler weather. This cloth is dense enough, that I feel the need to remove it on cloudy days.

We have 30% shade cloth over our propagation tunnel and one other tunnel with a mix of annuals and perennials. The 30% cloth is light enough for us that we see a nice reduction in heat, but don’t feel compelled to remove it with changes in the weather.

Why not just leave the denser cloth on all the time? I worry a bit about an increased chance of disease - powdery mildew, especially. The tunnels are pretty nice for preventing mildew as long as they can get hot enough. Powdery mildews generally do not survive well at leaf temperatures above 90F.

This season, we stretched some extra pieces of shade cloth (the ends of the shade cloth from each of the tunnels) across two tunnels to make a shaded area for growing potted plants between them. The pots are sitting directly on black landscape fabric for weed suppression. We knew that without some sun protection our dahlias, lilies, eucalyptus, and other shrubs waiting to be planted in the field would be suffering. We think of this space as a little plant nursery pavilion. And- it’s a lot nicer for us to work under, too!

Our shade cloth was sourced from Farmer’s Friend.

I hope that helps! Let me know if you have any questions.