Amending in-ground soil when planting...

[TorontoJoe]

For some time I've been using a potting mix that seems to work well from me. I typically make a 5-2-1-1 (Pine bark fines, Perlite, Peat moss, composted manure).

I have a bunch of new trees going in the ground this spring where there was previously only grass. Based on previous excavations, I know I have a lot of clay below the topsoil. I'm wondering if anyone has any recommendations for amending the soil where I'm planting 2 and 3 year old trees? Do you think tilling in some sand and compost is adequate?

Also, how large an area? Something around 3'x3'?

I know there's single no magic bullet here...Just wondering what others are doing....

[FigMania]

I know where I live the Ag Extension recommends native soil as much as possible The soil is pretty dense clay. If too much decomposable mix it can and will rot in time and the level of the crown will drop. I buy a truckload of planter mix from the local landscape/rock company which is some native soil that has been mixed with a composted material from the landfill that composts home vegetation. Makes very nice soil for raised beds, etc. I then mix that soil with more native soil and plant so the crown is above the current level by a few inches as it will settle a bit. Prior to filling, I take a pitchfork and break up the inside of the hole so it is not smooth and helps penetration a bit. When I spoke to the Ag Ext people the said the shovel will create a slick bowl, sort of like plating on metal if you will, That can cause the roots to want to circle rather than find their way into the native soil. YMMV Good luck.

[TorontoJoe]

There's a place near me that offers what they call "Flower and Garden Mix" for $149 per yard. Seems a bit steep but they say it's all locally sourced and organic. I just don't know what their mix is....waiting to hear back from them

[zone5figger]

I would amend (not replace) your native soil in the planting hole with sand, pine bark fines, lime, rock phosphate compost and create a raised area by adding the eXtra stuff. 3' x3' sounds good.

[FigMania]

Here in this clay, the ag extension says do not add sand.. only helps to make cement from the clay. If it were me, I would check with your university agricultural extension.. assuming there is same in Toronto before doing anything. They are the local experts.

[susieqz]

not all extention guys are experts.
mine told me i couldn't grow figs here, but i'm doing it.

[TorontoJoe]

I hadn't considered going to our agricultural University. Good idea. There's also also my standby resource for this sort of thing. That being - retired people who've grown stuff around here for a long time... They just don't know figs...

[Noel Goetz]

Maybe someone could educate me. I don't understand the need to mix heavy or clay native soil into your planting mix, you don't want to impede your roots in your planting space (do you?) You are not training your roots unless you are possibly hardening them. In my hard clay As an experiment used a 3 ft. long 3/4" diameter concrete drilling bit set in a heavy duty hammer drill and made a series extra holes inside my hard clay planting holes to help keep roots from circling and reach down below bowl level. Probably a useless activity but we will see. Personally with figs I see no problem if your soil settles slowly in your bowl, it doesn't girdle your figs, when you add more soil into the hole (as it does with other types of trees) instead, I would think it would only encourage more roots from the main stem of your fig- but that is an opinion only, I have no actual experience. But as far as mixing in native soil into the planting mix again, can someone enlighten me?

[drew51]

Well the plant has to grow in native soil eventually, give it good soil, it will not leave. I have seem growers amend holes and the trees died. I know figs are different, but they are still deciduous trees like peaches. Closely related to mulberry too, I have seen where a guy had pure hard clay and the trees died, amending did work. If you build a large mound 6 foot high and wide it would work well. usually best to only amend from the top with mulch.
Here is one of many stories of girdling trees.

https://growingfruit.org/t/well-here-is-a-lesson-to-learn/606

[Joshj]

I agree with Drew51!

[TorontoJoe]

Noel - it occurred to me while reading your post that - while native soil might be a good idea in general - the trees that I'm planting are far from native to my area. So for the figs, it may not matter so much.

I rather her like your idea of drilling deep holes. My clay is pretty dense. I happen to have a big Hilti demo/hammer drill myself.....I may just use an old bit to go deep and loosen up the areas around the trees. Maybe pour in some sort of compost or worm castings. It beats digging. And I can't see how it could hurt... other than my neighbors pointing and staring at me....

[FigMania]

not all extention guys are experts.
mine told me i couldn't grow figs here, but i'm doing it.

"Can't grow" probably means it's not a plant designed for that zone. Makes sense.. but we can use alternatives to mitigate the cold the figs don't like. Wrapping with insulating material during the cold/freezing or bringing inside. Even living with dieback to the roots, which in some zones would still have to have protection.

There are different levels of "experts" at the Ag Ext. In my area, unless commercial in nature, we are referred to the Master Gardeners. None are expert on anything. However, the general training emphasizes not / or very little amending. I remember the first time we were taught this by UC Davis experts. It had to do with planting lawns. If one used a tiller to break up the soil and amend before planting.. the tiller scarified the ground. Almost like putting a glaze on the soil beneath. Once the grass seed sprouts and the roots reach the glazed ground below, the roots tend to spread along that layer and not do a good job of trying to go down.. hence a very shallow root system that needs extra water. My comments above had to do with the same idea. Unless the sides of the hole are broken up the same thing could happen. The roots are so happy in their current environment (potting soil or whatever you use) they do not really want to search further out.. and become root bound in the glazed hole.

I like the idea of using a soil drill as above to open areas of loosened soil for the roots to more easily break out of their "bowl".

[lilfiggy]

I am so jealous of guys and gals that just happen to have these great tools in their back yard. sigh.........I have a couple of shovels and "Dimos" who mows my yard who has been kind enough to dig holes for me. "Mans work he says" works for me LOL

[TorontoJoe]

It stands to reason that you have to have all the tools. Otherwise when a job needs to be done - you'd have to pay someone else to have all the fun...

[Bluemalibu]

Here in this clay, the ag extension says do not add sand.. only helps to make cement from the clay.

I've always been advised of this as well.

The addition of lots of organic material will help to loosen the soil, adding to the aeration of the roots as it decomposes.

[TorontoJoe]

Hers's a guy doing the drill thing...Mind you he's using a Bosch, whereby everyone knows a Hilti would provide for a better drilling experience....But that's for another forum....

https://www.youtube.com/watch?v=0r5EqOF1nV8

[Bluemalibu]

Thanks for clarifying, Joe... when you mentioned using the drill to loosen the soil in order to help the roots gain a footing, and to aid in drainage, I had envisioned drilling from inside the excavated hole, out into the surrounding soil in all directions. I thought that that was a great idea.

[Noel Goetz]

I drilled into the bottom and sides of my planting basins. It certainly can't hurt.

[WillsC]

I use to amend the sand here when I planted then in the summer had 21 days of at least an inch of rain a day......(welcome to Florida in the summer). It made the soil too wet for too long and I lost a plant I tresured due to rot.....never again will I amend to make the soil richer and now I just mulch.

[TorontoJoe]

This is really interesting. Ive always associated the addition of sand with promoting drainage. The idea being that it would behave like gravel. Is it possible the type of sand being used is a factor?

My assmption was that a mulch would retain water whereas it would pass over sand....

[WillsC]

This is really interesting. Ive always associated the addition of sand with promoting drainage. The idea being that it would behave like gravel. Is it possible the type of sand being used is a factor?

My assmption was that a mulch would retain water whereas it would pass over sand....

Sand has great drainage.......few years back had a hurricane come through and we got 27" of rain in 19 hours. 30 minutes after the rain stopped you could not find a puddle BUT what I did was mix compost and rotted bark in to the sand and doing so took away its excellent drainage, hence the wet stayed at the roots and rot. Some plants are susceptible to it and some varieties are not. The mulch keeps the soil surface cool and moist, a condition that soil nematodes do not like. As the mulch rots it releases its nutrients but does not make the sand drain slower.

[Billboard]

Hey im new to the fig thing but wouldnt gypsum work to break up the clay for better dranage? Dont know whats in it so i have no idea about it hurting the fig tree.

[Rewton]

There's always exceptions but I have mainly read that it is best to plant fruit trees in the native soil (in my case thin topsoil and heavy clay below) and not ammend it all. The reason is that you want to the tree to adapt to the native soil. Of course mixing in organic material that hasn't aged fully could cause other problems. If the soil in the hole is more fertile than the surrounding soil it is thought that the roots might tend to stay in that soil and not spread out into the surrounding native soil. Eventually you want a mature tree with roots that spread into the native soil quite a distance from the original planting hole and the sooner that happens, the better. Like someone described above, I also take a fork and introduce holes in the sides and bottom of the planting hole to encourage the roots to spread out.

[Rewton]

The one thing I do add to the soil for figs is lime.

[FigMania]

Hey im new to the fig thing but wouldnt gypsum work to break up the clay for better dranage? Dont know whats in it so i have no idea about it hurting the fig tree.

Gypsum helps a lot.. for awhile.. But long enough for roots to explore the native soil.

[TorontoJoe]

@ Wills - Wow! My I've been to Florida maybe 7 or 8 times. I guess I always come at the right time... 27" of rain in 19 hours - Insane! If I got 1/4 of that I'd be in my canoe. The sand seems to be a mixed blessing...Drains, but that water takes all the nutrients... I'm starting to get it now...Thanks

[WillsC]

@ Wills - Wow! My I've been to Florida maybe 7 or 8 times. I guess I always come at the right time... 27" of rain in 19 hours - Insane! If I got 1/4 of that I'd be in my canoe. The sand seems to be a mixed blessing...Drains, but that water takes all the nutrients... I'm starting to get it now...Thanks

With hurricanes if you happen to be near the middle center bands it is simply a never ending deluge. The arms are spinning so they are out over the warm Gulf of Mexico and suck up that water and down it comes. The fast moving hurricanes dont drop as much rain but the slow ones will just dump on you.

[don_sanders]

It may not apply to you but I always amend with compost. I love the stuff. If I had a lot of clay, I'd probably get truckloads of it to till into the soil.

[TorontoJoe]

I recently found access to tons (literally) of worm castings at dirt cheap prices. It's a bait worm farm 15 minutes from my house... 50lb bags at $4 each.... I think I'm going to be using this in all my gardens this spring....

[Go_Figger]

That's awesome! Do you know what they feed em?