Dr D told to dig a "hole 10 feet deep "....anyone ever really do it ?

[trioderob]

Dr D talked to me several years ago about digging a hole 10 foot deep and I assume he was telling me something to the effect that if you have crappy soil overpower the situation with heavy machinery - then refill the giant hole with primo soil .

of course this allows the plant to get a huge root system going in the immediate term.

you can envision how much easier on the palm this is then crappy rock filled alkaline soil.

it also begs some questions:

1) the practicality of renting the earth moving equipment to both dig the hole and filling with primo soil

2) the cost of the soil and the composition of the soil used as the fill

3) depending on how many holes dug - what to do with removed soil

then issues on how well the idea actually works

1) would you create a "sink hole" at the the bottom of new hole where water would pool

2) would palm sink over the years as organic rich soil decayed vs surroundings

3) would it be worth the grief and "monkey shines" to do it ?

4) would it allow you to zone push palms that were unprecedented in your zone

and then.......

1) did the Dr actually do it or was he messing with me

2) if he did do it - what was the payoff ?

and finally-

1) does the palm ever try to send roots past the huge hole into the native soil

2) how stable is a large palm from falling over if it is entirely contain in a large 'plug"

3) could you send a irrigation system / fertilization system deep into the hole before adding the fill soil

the possibilities boggle the mind........................

some guys are "box planters" .....anyone a "hole digger ?"

Edited May 12, 2015 by trioderob

[_Keith]

That'd probably work in Cali. If you dig a 10 foot hole in Louisiana you have. 9 foot deep pond.

[trioderob]

ok so here is the plug remover

normally it removes a plug and then a plug with a tree in it fills back up the void

what i am talking about is removing the plug and filling it with top quality soil - a small palm is then planted in this rich soil and spends its life there.

you have an option on how big a plug digger you want to go with.

Edited May 12, 2015 by trioderob

[trioderob]

and here is nice photo really showing what in the heck I am talking about - maybe something like this - if we want to talk

about something a little more realistic

this would get rid of the nasty rocks your palm roots have to fight thru , better ph and no 20 years of mulching to see results

Edited May 12, 2015 by trioderob

[trioderob]

so the punch line here is that normally you want the hole to be just big enough for the root ball - to encourage the palm roots to dig into the native soil. in this case you are creating an artificial environment that is big enough for the roots to spend their life in.

Edited May 12, 2015 by trioderob

[trioderob]

and here is some video :

https://www.youtube.com/watch?v=u8V886olvEQ

and of course the benefit depends on how bad your soil is.........................

Edited May 12, 2015 by trioderob

[Phoenikakias]

Dr D talked to me several years ago about digging a hole 10 foot deep and I assume he was telling me something to the effect that if you have crappy soil overpower the situation with heavy machinery - then refill the giant hole with primo soil .

of course this allows the plant to get a huge root system going in the immediate term.

you can envision how much easier on the palm this is then crappy rock filled alkaline soil.

it also begs some questions:

1) the practicality of renting the earth moving equipment to both dig the hole and filling with primo soil

2) the cost of the soil and the composition of the soil used as the fill

3) depending on how many holes dug - what to do with removed soil

then issues on how well the idea actually works

1) would you create a "sink hole" at the the bottom of new hole where water would pool

2) would palm sink over the years as organic rich soil decayed vs surroundings

3) would it be worth the grief and "monkey shines" to do it ?

4) would it allow you to zone push palms that were unprecedented in your zone

and then.......

1) did the Dr actually do it or was he messing with me

2) if he did do it - what was the payoff ?

and finally-

1) does the palm ever try to send roots past the huge hole into the native soil

2) how stable is a large palm from falling over if it is entirely contain in a large 'plug"

3) could you send a irrigation system / fertilization system deep into the hole before adding the fill soil

the possibilities boggle the mind........................

some guys are "box planters" .....anyone a "hole digger ?"

The first three questions in the first chapter suggest indeed that MD has to be disgustingly rich, but again better create something unique sailing through time, than collecting for example cars

Answer to first question of second chapter depends actually on the location of the garden (slope or plain) and the properties of native soil. I can not see how a rocky soil especially on a slope can be poorly draining. I, for example, drilled on a steep spot of a slope with loose soil an one meter (about 3 feet) deep holle backfilled with pumice. However much I water, it is more probable that water would reach ultimately the antipodes and spring out in richnorm's garden, than flood in the hole!

To the next three questions of same second chapter here is my experince: I opened an one meter deep and 2 meters wide hole once in my garden and used as backfill a compost soil. I planted there several Archontophoenix and a Musa bajoo. Never encountered any sinking of the palms, which did grow at a rapid rate. But it did not help much if not at all during the 2004 cold spell, which killed all palms growing on this spot. Of the last three questions, first one is purely theoretical because 10 feet (more than 3 meters) is imo an adequate depth for the roots of every palm at any size. Refering to the second question of last chapter, my Archos, never had any stability problems and as for your last question I apply already this method on a Medemia and a Jubaeopsis in my garden. To this purpose I use pipes stuck in to the plant's holes, and let run through the pipes the dripping system. It works fine sofar...

Edited May 12, 2015 by Phoenikakias

[trioderob]

[Moose]

and here is nice photo really showing what in the heck I am talking about - maybe something like this - if we want to talk

about something a little more realistic

this would get rid of the nasty rocks your palm roots have to fight thru , better ph and no 20 years of mulching to see results

South Florida soils would be laughing at such a piece of equipment as it bounced off our limestone. Never even seen one in this neck of the woods. We auger deep holes.

[trioderob]

that's brutal

Edited May 12, 2015 by trioderob

[Jeff Searle]

Yes....doesn't everyone do it this way?

[trioderob]

ok so looking at this Florida sinkhole it appears that a few organics in the backfill might do the trick

looks like the top soil is kind of minimal

no need to go this large on the hole tho

Edited May 13, 2015 by trioderob

[NorthFlpalmguy]

Interesting but I would only think it applies to California-type soils. I wonder what results would say, a 80/20 mix of potting/native soil would yield within a 3 ft radius and the rest native?

Those big tree spades trucks are for up north generally. The limestone plus big oak roots would wreck those spade blades/hydraulics I bet.

[Josh-O]

[Matt in SD]

Dennis Willoughby has very nice soil, and I can't remember how he said he knew this, but the soil is uniform from the surface down to 8 feet or so I think is what he said. I would say that his garden supports that really deep, really good soil definitely leads to good growth. But I think that the depth your talking about (and what Dennis has) is complete overkill.

I wasn't too impressed with the state of the soil when I started my garden. No tests or anything, but it was compacted, heavy, clay in some places, sandstone in others. I rented an excavator and basically went around the entire property digging as deep as it would go (3-4 feet probably) and mixing everything up. I had spread a lot of compost over the top before this so that got mixed in. I'm pretty happy with the growth I'm getting in most areas. So that was only 3-4 feet and I didn't even replace the soil, just loosened it and amended a bit.

I planted a palm in an area where I could only dig the hole deep enough for the roots from the pot (a 7g pot) to sit on a very solid sandstone base (I couldn't even chip it with a pry bar). It has grown very well.

And all those gardens around Hilo where the palms look so perfect have basically no soil at all, definitely nothing but solid rock more than 3 feet from the surface.

I really don't think that most palms care much what is more than about 3 feet below the surface (as long as the roots can spread laterally). So in the end it's probably easier to amend, or strip and replace the soil down 3 feet over your entire garden than to dig a 10 foot hole for every palm you plant.

And if you're going to fill the planting whole with 100% non-native soil, you better know what you're doing. I've definitely seen cases where people tried to do raised beds with 100% non-native soil, and the plants did very badly...

Matt

[rprimbs]

I remember reading an article in "Mother Earth News" -- back in the 70's -- about an experiment with fruit trees. They amended several holes with different things, and planted some in holes that were not amended at all. The article claimed that the trees in the amended holes grew the fastest initially, but the trees in the holes that were backfilled -- with the same soil that was dug out -- eventually overtook them and did the very best. I've also heard people argue that you should not put fertilizer into the hole, but only apply it on the surface.

However I did dig a hole that was 3 feet wide and 3 feet deep for my Bismarkia. And that seemed ridiculously big to me! Since then the deepest I have gone is 2 feet -- and that was only to put down mesh so that gophers would not get the roots.

[LJG]

Rob, you need to recall that Mardy was referring to his place. His garden sits on a rock mountain basically. He had to blast out planting areas decades ago. For him he wanted 10 foot holes because it would be surrounded by nothing but rock. I would imagine if you dug down almost anywhere in Docs garden, you would hit rock 3-4 feet down outside the areas he blasted and built up over the years. I have seen many holes Doc has dug, and they are usually big enough for him to pot plant in a 25 - 45 gallon sized pot. So I doubt his 10 foot hole he was referring too was for each plant.

[Kim]

I notice the photo in post #10 is a montage. The guy in the cowboy boots has been superimposed on the image for some unknown reason. But entertaining, okay.

Holes I saw dug in MD's garden a few years ago were hand dug with ordinary shovels to maybe 4 ft. and had heat cables placed in the bottom in preparation for planting some cold-sensitive palms. They looked like really big holes to me, but for sure they were not anywhere near 10 ft. deep. He did talk about having used dynamite when his garden was first planted, but the authorities soon put a stop to that.

For palms to thrive, it can definitely be worth amending the soil and applying mulch, but the extreme measures described in the original post are not necessary. Some of the best gardens I've seen in the San Diego area had good soil hauled in. I'm not sure exactly how deep, but not more than 2 - 3 ft.

Edit: I would add that much of MD's success in growing palms would be attributed to the cold-air drainage afforded by his carefully selected hillside location in combination with adequate overhead canopy.

[trioderob]

not to mention the "rock dust" by dynamiting off the top of the hill....................palms love that stuff. ......

[DoomsDave]

not to mention the "rock dust" by dynamiting off the top of the hill....................palms love that stuff. ......

Also great asthma therapy.

[DoomsDave]

Hmm.

Deep soil is an advantage if you have it. Some plants, like Walnuts, really do appreciate being able to root way down deep.

Palms, well, maybe not so much. Many don't root that deeply. There are exceptions of course, but they seem few and far between.

Nothing tops river bottom silt. The best soil, period. Holds water well, drains well. It's like a fat bank account that's tort-proof with unlimited access for you. You (and the gophers) get a bit spoiled. I once dug down about 8 feet, still nothing but soil (in my first California garden). Walk by the fertilizer aisle at Home Depot and laugh at the poor schlubs loading up on Bandini.

But, you have to be in a river bottom (like the Nile or Santa Ana River floodplains) or uplifted river bottoms on hills. The former are plagued by floods and cold air settlement into them. The latter are hard to find, but great when you do, providing they don't have a lot of rocks, etc. mixed in with the silt.

Getting nice deep soil if you don't already have it is a lot of work. Clay is good if it's amended. I hand-dug about half of my half-acre on a hill to a depth of about 2 - 3 feet, and it was arduous. Mr. Spinal Column appreciated the exercise - up to a point. I think I got past that point. Palms have mostly grown well.

Sergio (Gotpalms) avoided all that and just planted on top. His results are great, too.

If you're a building contractor, and can easily get a few 'dozers and a hard-hat crew to doze and dig, great. If not, Sergio's idea seems to work.

Always willing to learn something.

[Alicehunter2000]

I put three foot of mulch in a 20x100 ft space that was ufortunately covered back over with 1-2 ft. Of beach sand. Really wish the contractor would have mixed up th layers. Everything has sunk down some but everything was planted high. The worst thing is that somtimes holes will open up when watering. Luckily they quickly fill back up with loose sand. I have a hard time keeping small stuff watered as the roots don't reach down to the good layer. I try to dig down to the good layer and backfill around small stuff with potting soil.