Structure for Frost Cloth

I need some input on building a structure for my fruit trees.

Late frosts destroy the fruit on the trees, so I need a structure so I can lay frost cloth.

The two apricot trees are side by side. The bigger one is 13.5' h x 15.5' w.

I watched a video in which a PVC "box" was built for this purpose--but the trees were smaller, my trees may be too big for such a PVC box.

Prune it down some.  Maintain it to your height or a couple foot above.

2 or more U-shaped hoops of 1.5 inch or 2 inch poly pipe would probably stand up okay if you arrange them in an X and tie them together at the top and set the bottom ends over some pegs driven into the ground. 1 inch poly pipe might work but it would need to be the heavier-walled stuff.

Instead of using PVC try using Metal Conduit (EMT). PVC gets brittle.
1) You can hammer each end flat, drill a hole through it and bolt two EMT together.  Build a box out of this since it is easy to bend.  
Also
2) I have found that a 1/2 inch conduit will fit inside a 3/4 inch conduit so I cut a 3/4 inch into many small 12 inch long pieces and slid the 1/2 inch tube inside, drilled a hole and put a screw inside. I would hammer the center of these small pieces so I could bend the 3/4 inch tube into 90 degree bends easily.  I expect these to last long time.

Dennis Bangham wrote:Prune it down some.  Maintain it to your height or a couple foot above.

I do not know how to prune it really. I have done some pruning, after having watched some videos, but I do not really have confidence in my knowledge, though I have considered taking a few of the very large branches and air pruning them and starting new trees with them.

Dennis Bangham wrote:Instead of using PVC try using Metal Conduit (EMT). PVC gets brittle.
1) You can hammer each end flat, drill a hole through it and bolt two EMT together.  Build a box out of this since it is easy to bend.  
Also
2) I have found that a 1/2 inch conduit will fit inside a 3/4 inch conduit so I cut a 3/4 inch into many small 12 inch long pieces and slid the 1/2 inch tube inside, drilled a hole and put a screw inside. I would hammer the center of these small pieces so I could bend the 3/4 inch tube into 90 degree bends easily.  I expect these to last long time.

I did watch a video recommending Electric Conduit over PVC, and I suppose it sounds like a good idea.

What do people normally do with Apricots to save the fruit from late frost?

Dennis Bangham wrote:Prune it down some.

Would you say air layering some of the larger branches off would best be done before or after the harvest?

I have no experience in air layering.  I tried stool layering once but it was not successful.

Some people paint the trunks of trees to slow their spring awakening.
Other ways to create shade would be water barrels, shrubs or raised beds.

Would you even need a structure?  Have you tried sewing the frost cloth pieces together to make a large enough cloth to go over the top of the tree(s) and with the help of a friend and a long piece of pvc pipe, pass the cloth over top of the tree and tie the 4 ends down to the ground or maybe to stakes set at 4 'corners' of the tree.  Maybe put a string of lights wrapped around some of the tree limbs under the frost cloth to generate some extra heat? In southern Calif orange orchards they would run large fans in the orchards on nights when a frost was expected. I'm not sure how that protected the trees. Maybe someone else would know?

William Bronson wrote:Some people paint the trunks of trees to slow their spring awakening.
Other ways to create shade would be water barrels, shrubs or raised beds.

I think I've seen that.

Is that what that's for? Do some people do that to prevent sunburn?

Do they paint it with the white paint? Do they paint the lower part of the trunk, the feet of the trunk that is nearer to the soil?

Denise Cares wrote:Would you even need a structure?  Have you tried sewing the frost cloth pieces together to make a large enough cloth to go over the top of the tree(s) and with the help of a friend and a long piece of pvc pipe, pass the cloth over top of the tree and tie the 4 ends down to the ground or maybe to stakes set at 4 'corners' of the tree.  Maybe put a string of lights wrapped around some of the tree limbs under the frost cloth to generate some extra heat? In southern Calif orange orchards they would run large fans in the orchards on nights when a frost was expected. I'm not sure how that protected the trees. Maybe someone else would know?

1. I don't want to knock the flowers / fruit off of the trees (depending on when the frost comes).

2. Here in Northern AZ it can become very very windy. The structure would help keep the cloth in place to prevent the removal of the heat it is supposed to trap from the soil within the cloth.

I saw a video of a guy who made a pvc "box" for his trees, but they were much smaller. I'm thinking maybe I should just do that.

I can just make it so that I can reuse the pieces to make smaller boxes because I'm considering air pruning some of the larger branches (as also was recommended here) and planting them as their own trees.
Along these lines, I know they say the safest time to prune is when the sap is pushing outward into the branches, but I was thinking I wanted to harvest this year (I'm injecting compost into the roots, so I'm invested in getting the harvest), and then do it (I'm assuming air pruning will either significantly impact the harvest or negate it altogether).

I'm not sure of the tree painting procedure, it seemed fussy so I did not research  it further.


For an enclosure,  consider a single pole right next to the tree, with a big hoop of PEX pipe hanging from it, forming an "umbrella".
Drape it with frost cloth, and bury the edges, or hold it down with ratchet straps.

William Bronson wrote:I'm not sure of the tree painting procedure, it seemed fussy so I did not research  it further.


For an enclosure,  consider a single pole right next to the tree, with a big hoop of PEX pipe hanging from it, forming an "umbrella".
Drape it with frost cloth, and bury the edges, or hold it down with ratchet straps.

1. What kind of damage to the roots are we talking if I put a pole down into the ground next to the tree?
2. Would you have any examples (images) of this setup you could share here?

Thanks!

I don't know how much damage it might do.
I've only done it on a small scale:

For the pole, it could just have cross or plus shape at the base so it has some stability, then attach to the tree?

How do you attach the hoop?

William Bronson wrote:I don't know how much damage it might do.
I've only done it on a small scale:

I guess with a cross shaped pvc connector at the middle i could have extending arms then bend four pieces of pvc into four connecting pieces to make a hoop around.

Denise Cares wrote:In southern Calif orange orchards they would run large fans in the orchards on nights when a frost was expected. I'm not sure how that protected the trees. Maybe someone else would know?

I'm not sure, but I have noticed too that if it is breezy when we are cold overnight, we are less likely to see ground frost than when the air is still. It does seem counterintuitive - think of wind chill?