Denise and Rick (Bed 29 & 25) have a great frost cover system. Their system is tall enough that large plants such as cabbage, broccoli and other cold weather crops can be covered easily. The sides of the structure go straight up as well. Rick created a PVC bar to put over the tops of the poles that are hold up the trellis for the peas.
(This is important because you don't want anything rough or pointy sharp that can rub a hole in your frost cover!!)
The frost blanket Denise is using came from Gardener's Supply -
The Garden Quilt It is an excellent size for using on large plants as it is 20 ft x 20 ft and is good down to 24 degrees. This size blanket easily goes over the trellis for her snow peas with room to spare. Territorial Supply also has really heavy duty Frost Blankets/Row Covers -
Territorial Seed Frost Blanket Whichever you buy, just be aware that a 6 foot wide blanket will NOT be wide enough to cover your ribs length wise (end to end.) You will have to piece it together if you use 6 foot wide cloth which is very tedious and not as secure.
Denise's Most Excellent Row Cover Structure with Blanket for Bed 29
This picture shows the ribs of the structure for Bed 29
Materials Needed to make the ribs
The ribs in Bed 29 are taller and used these materials to make one rib.
(The height from the ground to the top of the hoop ranges from 36" to 42" tall)
10 ft section of 3/4" SharkBite PEX tubing (plumbing supply section $4.98 @ Lowe's & Home Depot)
1/2" inch standard rebar (2 ft section - $1.97 @ Lowe's, $1.60 at Home Depot)
(the plumbing tube needs to fit easily over the rebar you choose)
Rick cut off 1 to 1 1/2 feet of tubing to form ribs of the desired height to fit the frost blanket Denise wanted to use. However, you can use all of the tubing if you want.
The ribs in Bed 25 are shorter and a different size tubing was needed to get it to bend properly for a short rib.
(The height from the ground to the top of the hoop is 27" in this bed but you could make your ribs taller)
10 ft section of 1/2" SharkBite PEX tubing (plumbing supply section $1.60 @ Lowe's, $2.85@ Home Depot)
3/8" all- threaded rod (2 ft sections $1.97 @ Home Depot)
(the plumbing tube needs to fit easily over the threaded rod/rebar you are using)
Rick cut off a 2 foot section of tubing to form these ribs. You can use all of it if you want.
Rebar with tubing sliding down onto it
Pound the rebar into the ground so that approximately 6 inches is above ground. Do this to both sides of the bed. Stick the end of your tubing rib over the rebar and push the tubing all the way into the ground (approximately 11" to 12" depending on the hardness of the ground/depth of soil in your bed.) Then put the other end of the tubing on the 2nd piece of rebar. One rib is now constructed.
PVC structure
This is the "structure" that Rick created out of PVC pipe and fittings to hook over the stakes holding the trellis in place. Notice the ROUNDED corners that prevents wear and tear on the frost blanket!!
The last piece(s) you need are clamps/clips to hold the frost blanket attached to the ribs of tubing. You can order the
Territorial Garden Clip System from Territorial Supply but they are rather pricey.
If you enlarge the picture you can really see the white clip that Denise is using that she got from Territorial Supply. As well, notice the clamps with red handles that were used to secure the excess fabric to keep it from flopping in the wind. The rocks she used are wrapped over and over in the bottom of the fabric.
Or you can make your own. Per Rick's instructions buy a 1 foot long piece of 3/4" white hose. Cut the white hose into 1" pieces. Cut one side of the hose piece. Make a 2nd cut and remove a small slice of the hose to form a C shape (but more closed than a capital C). This forms your clip that you will use to clamp your frost blanket to the ribs. You want a small piece to be removed so you can easily clip it on the tubing rib but not so much that it doesn't tightly hold.
Create one and test it out before you make all of the clips.
You need to make sure ALL pieces of your blanket are clipped down, clamped down, etc. Use rocks to anchor the bottom to keep the cold air out and to keep the wind from ballooning your structure. You may need heavy clamps to hold some of the extra fabric together on the sides.
(This post was updated Nov 26, 2012 with Denise's comments/corrections and a picture of the clamps & clips.)