clay soil with gravel in it + 3 hrs. hot, hot sun

Dalton, GA(Zone 7a)

(Apologies in advance for the length of this!)

Does anybody have clay soil with gravel in it? This area was actually an extension of the driveway when the former owners lived here. When I moved in, 12 yrs. ago, I did some shallow amending (too hard!!) and planted some shrubs which have done well. But now I'm taking out several shrubs and want lots of tall flowers (2 - 4 ft.).

In addition to inhospitable soil, the area has become very shaded (altho it's bright shade). It gets no morning sun once the tree canopy closes. Parts of it get abt 3 hrs. of broiling hot afternoon sun but not all at once - half an hour here, an hour there.

Thirdly, there is a lot of tree root competition. There is a large, mature photinia plus 4 tea olives I planted which have become trees. And a few shrubs.

I need tall perennials that will flower in mostly shade but not burn up in the hot sun *and* be able to withstand the inhospitable soil and root competition.

I've posted parts of my problem on other forums and made a few decisions already, but have not brought up the gravelly clay soil. So what say the shade experts abt which flowering perennials will thrive (or almost thrive) in my soil?

One decision already made is that I am not going to do raised beds with the possible exception of a small experimental one. Also, bcs of the tree roots, I'll probably not use hostas (unless I do the small experimental raised bed). And finally some of the suggested perennials I'm considering are day lilies, shade tolerant echinacea and rudbeckia, astilbe, sages and salvias. I just don't know if all of these would work in my soil altho I think the day lilies will.

Must go pick up from school. Looking forward to what anyone has to say.

Staten Island, NY(Zone 6a)

I think that Black eye Susan, Coneflower , Phlox, Shasta Daisy and Asters will do
well in that area. From my experience I have most of them growing in total evening sun except the Daisy that is growing in morning sun . You can also try some . perennial Hibiscus they come up nice and tall and bloom beautiful and they like lots of sun . Yes day lilies will do well as I have them in the evening sun area and they are still giving me blooms . It's amazing to hear someone else dealing with clay soil and I have the root system too. I do not have a tree in my yard but I have to deal with roots from either neighbors on the north and south side of my property . I made beds and added peat moss and pot soil and compost But I am still encountering the roots here and there. I am at this place 8years now and I make my own compost bin and I am constantly adding compost. So good luck and enjoy the gardening.

Dalton, GA(Zone 7a)

So you think 3 hours of sun is enough for a hibiscus to bloom? I read that they need 6 to flower well. I love them tho and am looking to replace the Kopper King I lost in my sun garden.

I have always wanted to grow asters but to my knowledge have never seen them offered for sale in my town. I'm terrible at starting from seed. Maybe I'll look on line.

I feel your pain with neighbors' tree roots. On one side of me there are two pin oaks planted right on the property line!

Thanks for the suggestions.

Staten Island, NY(Zone 6a)

How about if I mail you some Aster plants. Send me a DMail with your info

Dalton, GA(Zone 7a)

You are so generous! If they are blue or purple I will take them. Those are the colors I'm missing for the new garden. I found out that Home Depot may carry them after all but they don't have any right now and you never know what colors they'll be when they come in.

I'll dmail you later and we'll see what I can send you in return.


Hobart, IN

Chiming in here. Be careful with the Astilbe in hot, dry areas so they don't turn crispy. They do like a good soil and, if exposed to much sun, they'll need additional moisture and a good mulch.

Lake Stevens, WA(Zone 8a)

I have similar clay-with-rocks-and-gravel. Yuck. It does make plant choice difficult.

The hot-hot sun but for a limited time does really restrict your choice of plants. The one tall perennial that immediately popped into my mind is one I planted in my dry shade garden, under a pine tree, and it is doing great. The kind DGer who traded it to me sent me two, so the other is in a much more sunny spot. It is a daylily Hemerocallis fulva var. flore pleno. This is a sterile double or triple daylily, which is mentioned as invasive in some locations, I must warn you. I read about it in a book called 'Planting the Dry Shade Garden' by Graham Rice. It is quite tall, blooms in flushes all summer into fall, even in shade. Thus far, in my dreadful location, it is not invasive. The foliage is not terribly attractive, but one can't have everything. From a distance it really brightens up a dim spot. Here are some photos of the daylily.

In a sunny spot but with the same crappy soil (when I first planted I actually chipped out holes with a hatchet), truly tough survivors for me include:
Geranium x magnificum is over 2 feet tall in bloom. I divided it this spring (it was over 6 feet across) and planted divisions in part sun. So far they look fine, I don't know how well they will bloom, but it is listed a being fine for sun or part shade. I will let you know next June.
Coreopsis 'Jethro Tull' is about 2 feet tall, remarkable survivor (I have tried a dozen Coreopsis, this is the only one that lives). It blooms for about 6 months!
Achillea 'Coronation Gold' about 3 feet tall
It is remarkable these have survived in such an inhospitable spot, which occasionally severe neglect from me (last summer they got no water at all for over a month).

I have found in my clay Salvias and Sages just do not survive, but your climate is different enough you should probably try them, but I recommend you don't buy a lot the first year in case they can't survive. When I gardened on sand about a mile from here they were very happy.

This could be a really fun long-term thread. I have one in my local Pacific Northwest forum I call "My Dry Shade Garden" about the Pine tree garden, I update it periodically with a report on how things are doing.

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Dalton, GA(Zone 7a)

CindyM, I am trying the astilbe somewhat against my better judgement since it needs constant moisture. I bought 2 and was planning to put one in the dappled shade area and one where it would get some sun. But maybe I'll put them both in dappled shade. Everything I plant will be heavily mulched.

Pistil, looks like you've got a nice garden going there. And what I would give for a reliably reblooming day lily! I am going to look into that as well as your geranium and coreopsis.

I hit upon a great $1 sale at our local independent nursery and bought 22 of the gallon plants! Can you believe it? It was old stock they wanted to get rid of and there were weeds growing in them and tags were missing or broken - but, hey, who can resist a $1 gallon plant when starting a new garden? I brought them home, pulled out the weeds and watered deeply. In 24 hrs. some looked like a whole new plant and almost all looked much better.

Got black eyed susans, rudbeckias, echinaceas, yarrow, a meadow sage, a veronica speedwell, bee balm, 1 or 2 hostas, astilbe and probably 1 or 2 more that I've already forgotten. What a find!

Lake Stevens, WA(Zone 8a)

Oh that is a great find. I have a garden I made a few years ago, planting in summer which was when I got around to it, I got a lot of things for a buck, that I thought could hold the ground until the next spring ( Scabiosa) which are still great.

Hobart, IN

Nice haul! Sounds like you've got a nice big bed full of plants. Anyway you can mulch with lots of shredded leaves and grass clippings (but not if they contain weed or insect killers)? Add some coffee grounds if you got 'em. You might be able to slowly improve the soil.

Dalton, GA(Zone 7a)

CindyM, I will have a good many oak leaves soon. All over the yard! I have not mulched with grass clippings in the past. I thought they had too much nitrogen???? I know that in a compost pile, the browns and greens work together to create compost, but can that happen on a small scale like around a single plant?

Hobart, IN

Yep but keep them away from the stems of the new plants. If you mix your grass clippings (remember - no weed killer) with shredded fall leaves, you'll have a great mix. I wouldn't mulch with just grass clippings except for maybe in the veggie garden.
I'll have tons of oak leaves myself in another month or two. I don't rake much anymore because DH bags the leaves with the lawnmower along with any grass clippings (normally those get mulched on the lawn) and I stash them in big garbage bags over the winter for mulching next spring. I don't use wood chips anymore - too expensive and I never know where they're coming from.

Cleveland,GA/Atlanta, GA(Zone 7b)

Addressing the clay & gravel issue: I inherited several hundred feet of gravel road bed on clay when we acquired our cottage in N. GA.. It now supports a kitchen vegetable garden, herbs and flowers. The larger rock is from the granite mountain base. I got rid of the gravel slowly by making a sieve out of chicken wire and 2"x2" and straining out the dirt over a yard cart. Each year I expanded the space. I also amended which made the soil deeper, more friable and easier to strain the following year. Some areas were packed so tight a shovel bounced. I used a finger hoe there. The finger hoe is slow going but it does the trick to loosen tightly packed gravel. I put the gravel in large landscape pots and let the rain wash the dirt back into what was to become cultivated.

Hobart, IN

Now that's some real dedication! Kudos to you.

Dalton, GA(Zone 7a)

CindyM, unfortunately there is a little weed/grass killer in our grass clippings. I tried 2 or 3 "natural" ways to kill weeds and grasses where I wanted to enlarge a garden area (or kill weeds within it) but never had much luck. So I'm back to RU (GASP!) or something similar now. What would happen is I would neglect to tell my daughter not to mow the edges where I sprayed and inevitably she would mow within a few days or a week.

I only use wood chips in 2 areas at the front of the house bcs I want them to look really good. Everywhere else gets pinestraw but not enough of it bcs it's expensive, too!

Maypop, you are one determined person! That is an incredible accomplishment. Would love to see a pic of it. I used to have a lot of persistence when it came to gardening (I still pull out chinese privet seedlings 1 by 1 with a pair of pliers), but on the whole, I take the easy way out now.

Up until a few days ago, I had my heart set on large hostas and other plants that would likely not reach their full potential in this environment. Tho I wasn't going to get out there with a sieve, I was planning some backbreaking shovel work to get amendments worked into the soil. Then, after a couple or 3 forum discussions, I suddenly decided I didn't want to do all that work! So I went back to the $1 sale and concentrated on tolerant, tough plants. It will be a different kind of garden than I originally wanted, but I just wasn't willing to pay the price for that one.

Hobart, IN

Next time you want to enlarge a garden area, you could try the cardboard thing and then doing the lasagna thing on top of it.

Cleveland,GA/Atlanta, GA(Zone 7b)

No amount or type of mulch would have helped my gravel situation. #1 photo is an example of what was inherited and #2 is the current entry to the cottage which has been worked on for just the past three years. There are small areas good enough to grow in ground and the remainder is faked in pots The cone flowers have actually done great with limited sun. Tricyrtis does well too. Gooseneck loosestrife is good but some consider it invasive. Maybe in good soil and sun. Otherwise, it is easy to pull. #3 is the kitchen garden this past April. It's taken over twenty years to reach this size and have soil conditioned like this. I till some years and don't others. I've got a tractor but don't use it in the garden because of the weight. #4 is from June. The last is end of July or early August. Anyway, I still have that original finger hoe plus a longer handled one. It is a most useful garden tool as I've actually excavated around rocks weighing over a hundred pounds until I've been able to angle a shovel. Did you ever wonder why archeologists and geologists work with such small tools?

I have lots of plants to share, including hostas, if you are interested. Just DM. You'd have to come to me and dig. I hosted RU's for four years but have not done one in a while. I'd mark off what people could dig and provide tools and pots. Same goes if you want to make the trip.

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Hobart, IN

Beautiful results for all of that hard work!

Dalton, GA(Zone 7a)

CindyM, I remember the term "lasagna gardening" from my first stint on DG but I'll have to look up how to do it. I knew I should have gotten back on DG sooner! It might be similar tho to what I started out doing in the spring. I was reclaiming a garden bed I made abt 9 or 10 yrs ago and then, after a few years, totally neglected. All the perennials had died but there were 3 mock orange shrubs and 2 ground cover roses that had survived.

It was covered with grass and weeds. First I put down 12 - 15 layers of newspaper. Covered that with organic matter and covered that with mulch. Weeds grew through it and I used RU on them to make sure they were killed to the root. The lawn grass kept growing inwards into the border of the garden underneath the newspaper so I shot it with RU, too - over and over - especially when I decided I needed an extra few inches. Without a barrier, I think I am doomed to constant spraying of the border. Actually, the same thing happens when I do have a barrier!

I just uncovered the bed this week and started planting in it. So I'll know pretty soon if or how well the newspaper covering worked.

But back to the RU. Only a very, very small percentage of the grass clippings would be contaminated. But that makes them all unusable?

Dalton, GA(Zone 7a)

Maypop, your pictures tell quite a story! And I LOVE the entrance to the cottage. I'm so glad you had the foresight to take a "before" pic. Tomorrow, I will take one of the garden area I am just starting on.

Dalton, GA(Zone 7a)

P.S. Maypop, I'll contact you if I get down that way. Thanks!

Saint Louis, MO(Zone 6a)

FY, I always hate to wade into the RU debate, since so many people have such strong opinions about it. I wouldn't think RU-treated clippings would harm anything after composting. Just my opinion.

Hobart, IN

Treading lightly here - perhaps I'm a little more finicky than most as I live next to wetlands and a creek and there are some reports of RU taking longer to break down in water than originally thought. Because of generally conflicting information, I prefer to be rather safe than sorry. Not preaching, just explaining.

Dalton, GA(Zone 7a)

Thanks, ya'll. Yes, people do have strong feelings one way or the other. Don't want this thread to become a weed killer thread so I'll just ask if anyone can point me to a good thread on "natural weed killing"? The ways I have tried don't kill the roots and I got tired of pulling the same weeds week after week.

But good for you CindyM, for protecting the water!!

Hobart, IN

Instead of pulling weeds (unless you're sure you can get all of the roots), you could use a sharpened garden hoe to slice the plant off at the soil line. Some say it depletes the energy in the plant having to constantly regrow. One of my faves is a flame weeder which is kind of fun to use. Don't use it in the lawn though as it can be non-selective. :) I wouldn't use vinegar - while it can be effective, too much can change your soil for the worse. There's an organic weed killer called Avenger but I haven't used it much. It's also non-selective. I also have a garden knife that I use for some weeds. Wait until it rains enough to saturate the ground and then tackle a section at a time, digging up the weed roots.

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