Posts Tagged: cloth
Beat the Heat with Shade Cloth
It's summertime! Our gardens are in full swing, tomatoes are beginning to ripen, berries are mostly done, and everything is lush and green. But beware, your plants can sunburn just like you. Sometimes we all need a little break from the heat, especially in the central and eastern portions of Contra Costa County where daytime temps regularly exceed 90 degrees.
Sunshine is necessary for plant growth, but too much can stress plants. Shade cloth (also called shade fabric) can block excessive sunshine and heat and will:
• Lower temperatures
• Reduce heat stress
• Prevent sunburn
• Reduce evaporation from the soil and the plant
• Reduce water needs
• Extend the growing season
• Expand the type of plants that can be grown
Selecting shade cloth
Shade cloth can block between 20% and 90% of the sun's rays reaching your garden beds, also called the transmission rate. A 30% shade cloth will reduce the sunlight reaching plants by 30% and will let 70% of the sun's rays in. The transmission rates will be shown on the product at the store. Delicate seedlings and cooler season plants (lettuce and spinach) will benefit from more shade (50–60% shade cloth), while sun-loving plants like fruits, tomatoes and peppers would do better with less blockage (20–40% shade cloth). Shade cloth is sold two ways: from a roll with a predetermined width and a length that you choose, or in pre-cut triangle and rectangle shapes. Shade cloth also comes in a variety of colors—black, brown, green, shades of beige, white, and sometimes less-common colors.
Installing shade cloth
Shade cloth can be installed several ways, depending on your garden layout. It can be spread over PVC hoops, also called hoop houses, or other PVC structures and secured with zip ties, ropes/twine, bungee cords, etc.
A triangle or rectangular piece can be installed like a sail attached to building edges or poles over the garden bed in a tent-like structure.
A DIY Frame can be made from fencing, vegetable cages, etc. and shade cloth can be draped and secured over the frame.
Be sure to attach shade cloth securely so that it does not flap or slide out of place because that can damage plants.
The vast majority of commercially available shade cloth is made from petroleum products like polypropylene or polyethylene. You may find shade cloth made from natural fibers such as jute, bamboo, sea grass, etc. but this is less common.
Give yourself and your plants a break from the heat this summer and for many summers to come by investing in some shade. It can help you use less water, prevent sunburn and heat stress, and extend your growing season. Enjoy your summer!
For more information about shade cloth in the garden, see this link: https://ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=55005
Help Desk of the UC Master Gardeners of Contra Costa County (DLB)
Winter is Coming in the Garden
Signs of autumn are all around us. . .we've had some rain, trees are showing off their fall colors...
It's October--Time to Plan!
By Susanne von Rosenberg, UC Master Gardener of Napa County It's the middle of...
It's Oct 2020. (blankcalendarpages.com)
Broccoli seedlings. (organicauthority.com)
Lettuce starts. (roundrockgarden.wordpress.com)
Time to shovel prune. (jimmycrackedcorn.wordpress.com)
Fava beans as cover crop. Bees like them, too. (calphotos.berkeley.edu)
Hardware cloth, be sure to overlap edges. (northcoastgardening.com)
Vegetable planning. (morning chores.com)
Seeds have a use-by life. (leevalley.com)
Citrus Trees Frost Protection
Advice for the Home Gardener from the Help Desk of the
UC Master Gardener Program of Contra Costa County
Client's Request: Good Morning Gardeners! I drive by your beautiful community garden (MGCC's “Our Garden” in Walnut Creek) every morning on the way to my daughter's preschool in the Shadelands area. I've noticed that you've already covered your citrus trees for frost protection. I have a small backyard orchard with 5 citrus trees...4 of them with fruit on now, and I have not covered them yet.
I have these dark colored tree covers that I bought and use (basically a large cloth bag, kind of like an outdoor patio chair cover with a drawstring at the base of the tree), but the directions that came with them advise removing them by day so the tree can receive light. It's a hassle putting them on by night and taking them off each morning. What do you use? Do they allow light in and for how many days in a row can they safely stay on the tree without harming the tree? Can the same covers be used in the springtime when my mandarin is flowering to keep bees off and keep the fruit seedless? Thank you so much for your advice! Happy Holidays.
You probably noticed that the covers at Our Garden are white, and are designed to let some light through so they can be left on for several days at a time. You can buy such “frost blankets” at garden centers or online- one brand that I know of is called 'Agribon' They are a lightweight, non-woven material, and come in different weights. You also asked about using this for keeping bees off your mandarins: I would not use the heavier frost blanket for this, but you could use the lighter weight 'row cover' which is often used to keep various moths and bugs off vegetables. Most nurseries and/or hardware stores should stock this or similar types of frost cloth.
Here is a link to an online source which sells these “cloths”, and it has some good information on its use. This is a commercial link, and we do not endorse any particular business, but I include it as it may be helpful to you. https://www.groworganic.com/frost-and-sun-protection/frost-protection/frost-blankets.html. There are many other online suppliers that can be found by Googling “frost protection cloth”.
For now, the covers that you have been using most likely are doing a good job, but being dark in color need to be removed during the day to let light to the plant. If you can provide a frame around the plant to keep the cloth from touching the leaves, that will work best. Here is a UC link with helpful information: http://homeorchard.ucdavis.edu/8100.pdf
You also asked how long the covers can be left on. I can't give you an exact number of days, but the plant should be fine for a few days at a time. I personally use these covers, and I generally leave them attached to the framework, and try to pull them back on warm days to get some airflow and/or sunlight to the plant. I make hoop structures out of re-bar and PVC pipe, and find that kitchen clips (such as you would use for chip bags) are a quick and easy way to attach the cloth to the frame. You can see pictures of such a structure here: //ucanr.edu/blogs/blogcore/postdetail.cfm?postnum=22776 You can anchor the PVC hoops with 2 foot lengths of re-bar pounded into the ground (make sure the diameter of the re-bar is less than the internal diameter of the pipe!)
I hope this is helpful, and if you have further questions please don't hesitate to get back to us.
Happy Holidays to you, and good luck with your citrus.
Help Desk of the UC Master Gardener Program of Contra Costa County (SMW)
Note: The UC Master Gardeners Program of Contra Costa's Help Desk is available year-round (except the last two weeks of December) to answer your gardening questions. Except for a few holidays, we're open every week, Monday through Thursday for walk-ins from 9:00 am to Noon at 75 Santa Barbara Road, 2d Floor, Pleasant Hill, CA 94523. We can also be reached via telephone: (925)646-6586, email: ccmg@ucanr.edu, or on the web at http://ccmg.ucanr.edu/Ask_Us/ MGCC Blogs can be found at http://ccmg.ucanr.edu/HortCoCo/ You can also subscribe to the Blog (//ucanr.edu/blogs/CCMGBlog/)
Hot Hot Hot: Finding Relief from the Drought in Fall
"Me mind on fire -- Me soul on fire -- Feeling hot hot hot" are not just lyrics to the catchy one-hit wonder by Buster Poindexter. It's also what we've been thinking (and our plants have been feeling) this summer. Although as of September 22nd, the season technically shifted from summer to fall, the temperatures have remained in the mid- to high 90's.
The hot sun and high temperatures can be brutal on a garden causing plants and vegetables to wilt, and soils to dry out. This isn't only about the heat and sun though; when diminished water availability is added to the scenario, it becomes about the effects that all three combined have on the garden. The goal this year has been to keep a healthy amount of moisture in the soil using less water.
With the water restrictions still in effect, it's important to look at ways to grow a fall garden with less water. One way to do that is by using row covers or shade cloths.
Protecting the plants from direct sunlight by using row covers or shade cloth reduces the leaf temperature and plant watering needs (they don't "sweat" as much). This can raise the production of your garden and reduce your irrigating and fertilizing costs. Its also useful in protecting your vegetable patch from insects and birds.
Row covers are often used in the winter to protect plants from frost, and during the spring and summer months to block out the sun. However, consider using them during the early fall season to protect your newly planted "cool" season crops from the sun and heat. Row covers generally block out 15-30% of the sun, depending upon the thickness of the cloth.
With the autumnal heat we've been having, shade cloth, which is a little heavier, might be an even better way to go. It comes in a variety of colors and densities depending upon the amount of sun to be blocked and what vegetables or plants need protection. While light colored shade cloth will reflect more of the sun's rays and heat, expect higher temperatures under darker shade cloth, unless you provide ample air space.
Shade cloth requires a simple support structure consisting of PVC or metal bows that span one or more rows. The bows support the shade cloth over the crop, providing cooling shade and reducing water needs.
If you are planting a vegetable garden, understanding the light requirements of each crop may allow you to plant some crops in a naturally shaded environment. Lettuce, currants, gooseberries, spinach, cauliflower and most beans can grow in conditions with less than full sun. Under these conditions, water use needs will be reduced due to the natural cooling of the plant.
Even plants that require full sun and love the heat (80-90°), such as peppers and tomatoes, sometimes need shade cloth too due to the intense summer sun or heat. I placed shade cloth over my tomatoes this summer when the temperatures were especially high.
Shade cloth can be placed over plants during the hottest time of the day (11 am to 4 pm) to keep them from getting sunburned or stressed. Sun damage can result in wilted or burned leaves and skin. Many of the cool season crops will bolt or go to seed prematurely in higher temperatures, and leafy vegetables turn bitter in taste.
Seedlings and recently transplanted starters do best with reduced sun until they are established. Initially, a shade cloth with a 10% percent density is perfect for sun-loving plants; 30% density cloth is best for more sun sensitive plants. This weight of cloth can also provide some protection from the drying effects of wind. During the hot summer months, most vegetable garden plants require 40% to 60% percent protection from the sun. Even though we are now in October, given the high temperatures were experiencing, using a 40-50% shade cloth to cover the newly planted crops can help with reducing the temperature. Shade can lower plant and soil temperatures by as much as 10°F.
Row covers and shade cloth can be purchased at many garden centers or online. I purchase mine online because of the broader selection.