Growing fig trees in compost socks


#1

Compost socks, aka silt socks, are basically long tubes filled with compost, you see them around construction sites to control erosion. Although they are generally made from mesh material, landscape fabric can also be used to better restrict root growth and prevent weeds.

They have been used to grow strawberries and other fruits and veggies, but figs really shine when planted in them, the growth first year has been equal to planting a tree in fertile soil.

Compost can cause drainage problems in container mixes, but when used in compost socks it acts like a small raised bed. It can provide adequate fertilizer for the first year, and holds more water than potting mixes, simplifying care. To enhance growth in future years, holes can be made to allow some roots to grow into the soil.

Irrigation is easy, soaker hoses or drip tape work well, as would sub irrigation (compost has good wicking properties). Storage is no more difficult than standard containers, in fact, they are cleaner and can be stored on their sides without spilling any compost. If indoor winter storage is not an option then they can be tipped sideways and covered in their growing locations.

Rather than shuffling them in and out during early spring they can be laid on their sides and covered and uncovered.

Repotting these trees will take some ingenuity, but because fig trees are so resilient, there are several options that could work.

Here’s a few pictures of growth progression, these were stuck in late April.
6/12


6/26

7/7

7/15

7/21

7/25
8/4
8/4


Figs have no flavor
#2

How heavy are those bags?

Tony


#3

They can be pretty heavy. The compost should be packed in pretty well. A 4 ft. section of 8" diameter holds 10 gallons.


#4

Those look great, I wonder if making them out of landscape fabric would be possible. I think I will try it, but use tie wraps for the ends.


#5

A 8" diameter sock is just a 24" width folded in half and sewn. You can either cut the roll to the width you want and sew a somewhat continuous sock, or buy rolls that are the width of the length that you want and wrap the fabric around a stiff piece of cardboard that is half the diameter you need and then slit down the edge to cut a bunch at once. I guess is depends whether you would like to have the option to change the diameter or length more… The cuttings stuck in 6" diameter socks seem to have grown a little better, but 8" is better for using transplants. 4" zip ties are the quickest way to tie the ends, something like rope makes it easier to grip the end though, I drag them around rather than pick them up.


#6

Thanks I will copy and paste your directions if that is fine. I have a folder with garden ideas and I am sure in the spring I will be frantically looking for this thread if I don’t.


#7

Here are some after being tipped over and covered for a 20f. night, excellent protection results. Took about 5 minutes.



image

The ones in the greenhouse (double layer, heater off) are still green.

Several made it to over 6 ft. and ripened a few figs, not bad considering the cuttings were not stuck until April.


#8

I cleared out all the leaves after they dropped and broke off all the immature figs. Then covered the ones in the 1st and 2nd pictures in the previous post with 2 pieces of ground cover that have 2x4s in between the layers so the outer cover isn’t in direct contact with the compost socks or branches. The roots still did freeze, and I saw some very mild signs of cold damage to green branches when I peaked under the covers today, the buds still look fine though… it looked like a breba was even popping out already.

The ones in the 3rd picture also had leaves and figs cleaned out but are just riding it out with one layer of ground cover and one layer of row cover, they were dragged to a shaded location and still covered in snow today, probably won’t check as often since I expect them to wake up later than the ones in full sun under the blak covers.

Planning to set them back up in March and then tip over and cover for any freezing weather during spring, although if they start waking up early I will have to start sooner or risk them getting leggy or rotting.

Happy they are looking good so far, it was below freezing for almost 2 weeks straight with multiple single digit nights and one below zero so I was a little worried.


#9

Glad you made it through that weather without too much damage! Thanks for the update!


#10

I am glad this thread was revived. I am now reminded to get out my fabric and start making these socks. Tipping them over is a great idea, when the cold snaps start it is easier to cover while laying down than standing straight up, and the problem with pots is then the dirt flows out.


#11

Thanks for sharing the project with us. What is the diameter of the socks and how many years do you think you’ll grow the figs in them? Will you just give them a hard prune when dormant and keep them in the socks long term?


#12

I’ve used 6" and 8" diameter socks so far, and will probably try 10" this year. Seedling from 2 years ago were congested in their 8" socks this year (though most are buddied up in a single sock), so they will either be planted in the ground, “up-socked” to 10" or more diameter, or let their roots escape into the ground. Those roots will need to be pruned in fall of course, unless I can figure out some way they could still be tipped over with the roots intact… only let the roots out one side, excavate beneath them somehow… or something like that. Roots are more flexible so I think it might work in some cases.

As far as pruning the tops, I will probably train them something like espalier so they can lay flatter on the ground. The goal for these is earlier fruit, heavy pruning chops would push the crop back so I would not want to do that.

I have an 8yo tree in a container that is a central leader and was never pruned, it is always one of the first to ripen and will ripen all of its fruit in about 3 weeks. I’m loving the vigorous first year growth in the socks but would like them to settle down like this older tree which only grows about 6" a year now because it has about 20 lateral branches and seems to have lost apical dominance.


#13

“Up-socked” :grin:


#14

Checked them out today and saw some botrytis so I stood them up to get fresh air and pruned that off as well as a few branches with freeze damage that were probably touching the cover. Sap is flowing already, expecting to lay them back down and cover next week before it gets cold again.

This late summer cutting looks like it will make it even though it is as green as they come.

Most figs left on the trees look fine, not sure if they will try to ripen or not. A good sign laying flat on the ground and covering works well though.


#15

Here’s some of this year’s trees.
6/18, I’ve been watering with a sprinkler.


7/31, A lot of the later cuttings i stuck failed for various reasons so many of the ones on the left above needed to be started over.

Last year’s are doing OK, some got a little too dry, some are probably a little too rootbound.


#16

Got a full shot of the freshman class. Will be giving them more space to grow soon.


Peppers do OK in compost socks also.

Here’s a 2nd year GM171, loaded with fruit at about 7ft. tall. This tree is already outperforming its mother which has pretty bad FMV symptoms, not a single sign of it on this one though.