Shade Cloth Part I: A Sliding Scale
Years ago in the bonsai garden I put up what I thought was the best guess for shade cloth: 30%, meaning, 70% of the light passed through. After several years it was apparent that was not enough, and we switched it with 40%. Since then, in another area, we have put up 50%.
This led to reflection, as tends to happen with bonsai garden owners. We got some heat-nipped plants because my initial guess was off. And then, some summers days are a lot hotter than the average summer day.
The ramping up we did to correct our shade needs suggests a few general ideas, if you’re wondering what percentage of shade you need. For starters:
- Consider choosing shade cloth for the extreme summer day, not the average summer day.
- If 40% is your guess for the average summer day, then consider 50%.
- If under-shaded, one toasty day can roast trees beyond recognition
30% shade cloth
How do we arrive at that initial guess? This line from a manufacturer made me smile: Usually a shade percentage of 30-50% is ideal for vegetables, while 80-90% is ideal for sheltering people.
As a general sliding scale for bonsai, to be adjusted according to climate:
- 0-30% for sun-loving conifers, like pines and junipers
- 40-60% for shade-loving conifers, like hemlock, and deciduous trees and flowering accent plants
- 70-80% for moss, ferns, and non-flowering accent plants
In very hot climates with intense sun, some shuffling could happen. In those climates conifer bonsai, for example, can be moved into the 40-60% shade camp. Very small bonsai also need more shade.
For perfectionists:
- To nail the ideal sun/shade balance, consider overlaps
- A second shade covering, maybe 20%, can be pulled over the everyday summer cloth
- This can add critical protection for periods of extreme sun and heat
70% shade cloth, for shade-loving plants and extreme climates
In the middle of a big fry added sun protection banks.
On the other hand, overcompensating with shade does no favors for a plant. Plants have a specific light need, and if that is not met they can get weak. If 20% shade cloth doesn’t quite do it, resist the impulse to jump to 70%.
Next up in this short series on shade cloth, in Part II, we look at whether the color of shade cloth matters.
For more about shade cloth, try these previous posts: Podcast about Shade Cloth, and Not Just For Sun.
10 Comments
Here in Dallas, TX with summer high temperatures in the upper 90sar even a bit higher I use 60% shade for understory shade loving trees such as Japanese maples, hornbeams and American beech. But protection from the hot, dry southwest summer winds is just as important as shade
Thanks!
Some of our club members have really nice shade cloth but bought and use just bundles of it.
Any recommendations on a source or two that make a high quality product that is sold in small quantities?
Hi John, I had custom made pieces here in the States, and there seemed to be many competing companies making just what you want with great shade cloth. You send them dimensions and they’ll send you the cut and edged cloth, with grommets if you want that. The one thing most companies won’t do, I found, is a triangle or something not square. Otherwise lots of options.
A very good point, David, thank you for mentioning it!
I’m on board with shade cloth, but would like some information on designs for building a structure to support it.
My Hubby is an Architect, he built me a portable (but sturdy) structure with 8x8x8 half concrete block, 3/4 conduit, Aluminet and Bungie cords to secure the shade cloth to the poles. It really turned out fantastic. Poles were secured into the block with concrete. Able to withstand our Monsoons in Phoenix area.
Thanks for sharing this idea, very clever! Cheers!
Hi Maryann, yes, and sorry, it was a bit beyond the scope of this post, but a great idea for another one. I did a post about the structure we built: https://crataegus.com/2015/09/16/building-a-metal-shadecloth-structure/
Phoenix Arizona is the epitomy of heat, in fact if you can do Bonsai in Phoenix AZ. you can do it anywhere (minus the Arctic circle). Phoenix Bonsai Society loves the Aluminet.
Check it out, it makes the impossible, possible. Also, it should be noted that every yard is different depending on your surroundings.
Jenna Williams
Bonsai Queen
Education Director / Phoenix Bonsai Society
Hi Jenna, yes Aluminet is a good thing to look into in extreme climates. Thanks for the note!