I live in South - Western Oklahoma, myself, and have looked into various methods for planting in my area. I have a lot of red clay and dirt with large rocks mixed in, so my problems are pretty much the opposite of yours.

I would say that your water drains away too fast. Go out and buy some natural kitty litter (no scented stuff, no paper, just pure natural kitty litter in the cheapest bags you can get). This is pure Bentonite Clay. This type of clay works like any other kind of clay ... it absorbs and holds moisture, releasing it slowly over time. Another thing you can get, if you can find it in your area ... artificial snow (the type that you add water into).

One more thing that might help would be something to help aerate your soil, like Pearlite (an expanded volcanic glass that is extremely lightweight).

You'll have to pull your seedlings back up to be able to get under them, and dig the planting hole deeper and a bit wider, most likely... (around 3 - 4 feet wide, at least 2 feet deep, perhaps more to accommodate the main root). and then mix in topsoil, compost material (dead leaves and wood chips), pearlite, clay, and the artificial snow stuff if you can find it all together in a wheelbarrel or other large container. Take your re-mixed soil and dump into the enlarged hole, while someone holds the sapling in place. If you wish to add some fertilizer other than compost, you can feel free to mix it into the batch, of course. Afterwards, you'll want to stake your saplings to keep them upright till they can stand up on their own ... make sure to mound up the soil mix at least 3 - 4 inches around the trunk to account for natural soil compacting over time.

A somewhat appropriate mix would be ...

topsoil - 80%
pearlite - 5%
bentonite clay 5% (if you have the artificial snow, replace some bentonite with it)
compost 10%

take a had trowel.. and dig small 3 to 6 inch holes near a plant ... DISCOVER woisture level... act accordingly ... refill hole...

all your fancy descriptive soil words... really dont allow us .. to understand.. how water moves thru your soil ... so you have to find out ...

once you discover such.. then you can have an idea.. of how to water ...

ken

perfect, Ken.

Dax

The little (It's the more mature ones that can't take summer irrigation.

@Skie_M
I'm going to take your advice and improve the soil so I dont have to water it constantly. I'm not sure if I should dig them back out this late into the summer. The poor things are very sensitive to disturbance. But i'll start getting the right amendments in the soil for my future plants. Is there anything I can do from above without replanting? If I mix some perlite/clay/compost into the top layer of soil around the plant, do you think that would eventually make its way down or help retain water?

Personally, I'd be hesitant to amend the soil. Pretty much every scientific study in existence has shown that not to be beneficial, at least in the long run, for trees. If you do amend, do so sparingly! Hopefully, Skie_M's recommendations for 80% topsoil is for native soil (what came out of the hole). That is the absolute minimum (or maybe a little less than) I would consider if I just had to add some other amendments for some reason. I would skip the pearlite because I see no use for it in the application AND it will break down over a relatively short time anyway. I know nothing about artificial snow, but would personally want to know more before considering it's use.

Officially, I recommend not amending backfill when planting woody plants, however, I do sometimes add up to 10% composted bark fines. Even though no good studies that I know of indicate the benefit for such practice, I figure that small of an amount is less likely to hurt. Just don't over do it.

Ken's advice about checking soil moisture would be a prerequisite for me, before messing with anything. Unless you know what's actually happening, it seems unwise to try to change it.

Here is a link that might be useful: Planting a Tree or Shrub - see sections 7 and 12

P.S.

"The little ("

Actually, the size variable alone would have no impact, that I can imagine, on how much water they should have or could take. Of course, smaller plants with smaller root systems need more frequent watering in drier conditions. And smaller plants with shallower root systems might survive overwatering better in certain conditions by virtue of having their root contained in the upper layer of soil which might dry out more than the potentially saturated soil below. These situations are specific cases with associated vaiables, and shouldn't imply a general relationship between the size of the tree and the amount of water required/acceptable.

Yes, when I mentioned topsoil I wasn't meaning that you should replace the dirt with store-bought stuff! You really need to acclimate your seedlings to the local soil by only adding a small amount to the area right around the tree's planting site, just to give them a kick-start.

Soils that drain too well (being sandy and rocky) just cant hold enough water to make plants happy, which is why I mentioned the clay and the artificial snow (bio-degradable stuff, it's a man-made non-reactive acrylic that simply absorbs water). The pearlite is again non-reactive expanded volcanic glass to help the roots take in nitrogen by aerating the soil, just to help kickstart the growth of your trees.

I suppose if the trees have grown in a little too much already, you could just dig around them 2 - 3 feet and replace the top 3 inches or so with the mix I recommended or something similar, but the best results would be to get that clay and pearlite in and around the roots.

As I mentioned in my first post, my area has the opposite problem, being primarily rock and red clay ... it holds too much water and my trees keep dying. :(

Solution for me is ... build up berms made of store-bought topsoil mixed with the local dirt (60% topsoil, 30% local clay) and mix pearlite and fertilizers in as the last 10%. This will let the soil mix retain the proper moisture for the trees so that they can get established without drowning, and the excess water will run off the berms and down the hill. The problem with it is, it's going to be expensive and I dont have the money yet ... The even more expensive option for me would be to build up my yard to be 2 - 3 feet higher than all my neighbors with my chosen topsoil mix... If I dig DOWN .... all the water will run off their yards into my back-yard MUDHOLE and everything will die.

I want oak trees (to transplant to my uncle's land out of town), apple trees (some to keep, some to transplant), and cherry trees (those I'm keeping! :P )

@Brandon7
Thanks for the link. Good and useful read :). I learned a few things and it confirmed some of my beliefs. It suggests mulching 2-4 inches which I used to think was too much. I only have a very thin layer of oak leafs on my plants so that probably contributed to the rapid drainage. I'm going to build up the oak leafs to 3 inches which will probably help a lot with my problem.

@Skie_M
Thanks for clarifying about the topsoil. I thought you probably meant native soil but the confirmation is nice. I'm going to go ahead and replace the top few inches of dirt with the improved soil and see how that goes. :) It's nice that you're helping your uncle! Oaks are beautiful trees. ^.^

Oaks and apples are also a huge favorite with wild pigs and deer ... His hope is to improve his land so that deer will tend more to stay on it long enough in deer hunting season. Trees also provide decent shade cover in this southern heat.

In my uncle's case, I'll obviously have to set up a small fence/enclosure around the growing seedlings to keep the animals from just bowling them over and destroying them ... at least till they get to 12 - 20 feet high and can stand up to the abuse. If you have similar animals on the premises, you may wish to protect your trees in a similar manner. :)