Vampire Gardening

I have this crazy idea. I want to drive wooden stakes into my soil as an after-the-fact hugelkultur workaround. I have some 45 year old spent raised beds with mature trees growing in them. I want to bring them back to life. Here are the problems I'm trying to fix:

Water retention sucks right now in my raised beds.

Plants wilt quickly.

Trees are mostly avocado with shallow roots, plus a mature persimmon, lime and pine.

Nutrients are spent.

Big picture solutions:

Increase soil water retention with buried wood.

Increase mineral content with oyster shell and Decomposed Granite

Reduce soil evaporation.

Replenish nutrients with lots of compost and animal waste top dressings.

Increase tree root depth.

So I figure I need to get some wood and nutrients into the soil. I'm planning on top dressing with lots of wood and wood chips, compost, DG and somehow getting wood deeper into the soil. I should note I have access to an unlimited supply of animal manure, logs and wood chips, which when mixed are one hell of a combination!

First, I'm looking at the option of just pounding logs into the soil. EZ, but I'm limited to 2" logs and I'll have some soil compaction. How close should the logs be? Too close and I'll damage existing roots. Too far apart and I'm wasting my time.

Second, I'm looking at the option of getting out the post hole digger and auguring some big holes and filling them with wood, compost, oyster shell and DG. Labor intensive, but then again I'm a fitness kind of guy so labor is no problem. Again, how many holes and how far apart?

Finally, I'm planning on changing the watering schedule from every few days to once a week, deep. Then every ten days. Then every two weeks, etc. until I'm not watering any longer.

Ideas?

Thanks for the help!
-Greg in SoCal
18" ave annual rainfall
Mediterranean climate.

i have actually heard this used as a suggestion for poor lawns, to go around and drive sticks or stakes into the soil all over the lawn to hold moisture..so I don't see why it wouldn't work in the gardens..i have also heard of several people doing vertical hugelkulture where they bury the wood in up and down instead of sideways, hoping it will wick moisture up..my only problem with this is to keep the top of the wood covered so the moisture doesn't just wick away into the air and evaporate..

let us know how it works out

Sounds like a neat plan. My only hesitation is about the post-hole option. Though it will get more material into the soil, you run the risk of having a bunch of divots in the yard when the material rots down. However, this may be a feature and not a bug, as the divots will tend to collect run-off and direct it into the soil. Brad Lancaster refers to these kind of pits as "vertical mulching." Here's what he says in "Rainwater Harvesting for Drylands" Volume 2 Page 163 "Vertical mulching is the technique of filling holes or trenches with porous organic matter, without mixing mulch into the soil or covering the holes with dirt. Vertical mulching creates spongy conduits leading water quickly down to the root zones of adjoining plants where the moisture is released over an extended period of time. Holes or trenches should be constructed 6 to 18 inches away from the base of newly planted trees, 12 to 15 inches deep, and 1 to 2 feet wide. Trenches can range from 2 to 20 feet long, with the longer trenches used when you have a lot of mulch material to dispose of and localized runoff you want to harvest. The trench is always laid on contour."

Thanks for the info Brenda and Tyler.

Tyler Ludens wrote: . . . you run the risk of having a bunch of divots in the yard when the material rots down.

I see it as a feature. More like a french drain to sequester water. And since it'll be in a raised bed, I'll continue to top it with mulch.

Tyler Ludens wrote: Holes or trenches should be constructed 6 to 18 inches away from the base of newly planted trees, 12 to 15 inches deep, and 1 to 2 feet wide.

I'm planning on making them MUCH deeper than that. If I want my roots to grow deeper, I'll need some wood down deeper too. Any recommendations on how many holes? I've noticed many people just make one 6' hole and stick sewer leach pipe filled with gravel into it. I'm thinking more like a four 4' deep holes around each tree.

Yeah, I'm not sure why you wouldn't want to make them deeper, especially if they are smaller in diameter. At least four per tree looks good to me. Probably depends on how many trees you plan to plant and how many holes you want to dig!

Personally, I wouldn't use granite dust since it's twice as high (or worse) in radioactive stuff than other kinds of rocks. Granite is the stuff that leaks radon into people's homes and such.

Ground oyster shells are probably unnecessary in SoCal, AFAIK most of the soils that direction are already limey. Also, if you use rock dust, that's got plenty of calcium (and micros) already.

If you've already got raised beds, you might consider laying logs down next to them and then raking the dirt over them with a garden rake. Diatomaceous earth can also hold a lot of water (and air, too), although given how dry it can get in Cali it may still need some extra help (ie rainwater collection and drip irrigation).

I wouldn't pull out the posthole digger unless you intend on planting new trees. Nothing beats digging out a taproot hole and filling it with lots of goodies for planting new trees, though.

composted organic matter and ollas, maybe?

M Troyka wrote:Personally, I wouldn't use granite dust since it's twice as high (or worse) in radioactive stuff than other kinds of rocks. Granite is the stuff that leaks radon into people's homes and such.

I forgot about that one. Thanks.

M Troyka wrote:Ground oyster shells are probably unnecessary in SoCal, AFAIK most of the soils that direction are already limey. Also, if you use rock dust, that's got plenty of calcium (and micros) already.

Plus our water is limey too. I'll leave that out too.

M Troyka wrote:If you've already got raised beds, you might consider laying logs down next to them and then raking the dirt over them with a garden rake. Diatomaceous earth can also hold a lot of water (and air, too), although given how dry it can get in Cali it may still need some extra help (ie rainwater collection and drip irrigation).

I wouldn't pull out the posthole digger unless you intend on planting new trees. Nothing beats digging out a taproot hole and filling it with lots of goodies for planting new trees, though.

OK, I don't know if I'm being smart or lazy but I'm just doing a hugelmulch. I put down some 8" logs, covered them with wood mulch and goat manure, then I'm going to add a second layer topped with compost. I'll plant a few N-fixing plants and then I'll let the crawlies do the digging for me.

greg patrick wrote:OK, I don't know if I'm being smart or lazy but I'm just doing a hugelmulch. I put down some 8" logs, covered them with wood mulch and goat manure, then I'm going to add a second layer topped with compost. I'll plant a few N-fixing plants and then I'll let the crawlies do the digging for me.

Sounds like a plan. If you give it a good year before you plant any trees in it you'll get tons of crawlies. My hugel beds haven't even been down a year and they're already full of worms. I even had a baby snake take up residence in one (he was pretty angry when I had to move that pile). It would be interesting to see how plain hugel does with trees, I don't think anyone has done that specifically and reported on it yet.

My way definitely produces giant trees in adverse soil, although it's also a lot of work unless you have a really awesome post hole digger.

chrissy bauman wrote:composted organic matter and ollas, maybe?

I have never tried ollas but they look like they might work for me. I'll have to make a few and see how they work. Great idea!

OK, here's the finished product: I put down a layer of 8-10" logs around the existing tree, covered them in leaf/wood mulch and my world famous goat pen/straw blend, then put down three more layers. Topped it with some black compost and put in two deep rooting N-fixing Palo Verde tree volunteers I conveniently had sitting nearby (1), clover seed for shallow N-fixing and alfalfa for deep roots to get way down into the depleted soil.

My only concern is that things get too hot for the palo verdes because of the muckings mixed with the wood chips, but that will be a short term problem that will make the whole pile break down sooner.

I have another tree in the same bed that's not thriving either. I may dig some vertical mulch holes around that one to see if one way works any better.

To be continued. . .


1) I put three avocados in between two existing mature palo verde trees and they are thriving.

I love this idea. Hugelmulch! I think I may try a few of these beds. I have a bunch of spent rice straw so perhaps Ill broad-fork an area cover it with rotting wood and then cover that with the moldy rice straw. I'm excited to try this low effort method.

In the past week I've loaded dozens of 100+# logs into my trailer, cut and carried about five tons of wood, and buried about half of it in my garden. I like your idea of 'low effort'

I have dug near some baby trees and buried aspen logs in the holes and then filled them back in, and it seemed to give the trees a boost (was only this June/July so it is hard to tell if that is helping that much or not ..but seems to be)

I have two beds that have existing rose bushes that I want to phase out but don't have the heart to kill (some are upwards of 80 years old, probably) so last fall I covered their beds in sticks and rotted logs then mushroom soil and then put 4 inches of compact straw on top of that. This year I planted strawberries into the soil and they are doing amazingly well. The bed where I didn't have much mushroom soil left is still decomposing the wood but this top dressing hugelkulter works quite well for soil building, if you have the patience.

Brenda Groth wrote:i have actually heard this used as a suggestion for poor lawns, to go around and drive sticks or stakes into the soil all over the lawn to hold moisture..so I don't see why it wouldn't work in the gardens..i have also heard of several people doing vertical hugelkulture where they bury the wood in up and down instead of sideways, hoping it will wick moisture up..my only problem with this is to keep the top of the wood covered so the moisture doesn't just wick away into the air and evaporate..

let us know how it works out

Yes, I am looking forward to an update as well.

One concern I would have for those sinking posts in very dry hard pan areas would be that it may promote salt intrusion into the upper soil.

This is only a problem in certain parts of the world but worth thinking about and avoiding in locales where sub soil salinity can kill gardening plans. Folks in that situation should build their hugelkultur on top of the existing soil and never forget that they are standing only a short dig from a serious garden killer.

H, Greg...are you still out there? I am in the middle of digging a hole for a two year old cherry tree, a nicely rooted sprout and I have hit the pale yellow sticky clay...I had been hoping to bury wood in the hole but then I remembered your 'vampire Gardening' post and thought I would give it a try. This is all pick and shovel through rock work so post holes aren't an option for me. I am thinking of cutting at an angle some 3 to 4 inch logs into two foot chunks and drive them in with the maul around the tree after planting. Did anyone have some luck with this? I know another cherry tree that I planted at the base of a stump of a newly cut dying white oak grew very fast and lush last summr. I need an excuse to stop digging.

OK, here's my almost two years later update: All the avocados died. I talked to a professional grower and he said they wont grow well on hard Colorado river water or with animal manure top dressing. I have two left in 20" hugel-boxes watered exclusively with rain water and fertilized with leaf mulch. So far so good.

All my young apples planted in or around woody soil are dieing of fire blight too. Must have been in some of the wood I brought in.

Chopped and dropped the pine.

But its not all bad news. My plumbs, apricots, olive and berries are thriving and the existing mature trees have never looked better. We have severe drought conditions and I've still cut watering down to every two to three weeks.

The main learning points for me were to give things some time, be very selective about the wood I bring in, and to plant trees well adapted to my poor dry soil.

hmm, I think avocados prefer a humid climate, although your area should be warm enough for them. Your zone is way too warm for apples though, and also warm enough that you would need to use biochar in order to raise your soil organic matter much above zero. Dry is manageable, but that's not the way I would go about it, anyway.