Planting in decomposing granite-suggestions?

[Hollywood Palms]

Hi All,

My hillside is all decomposing granite-DG, in short. Bougainvillea, oleanders, plumerias, etc. all go straight into the hill with no or very little amendments. Cactus and aloe grow with no amendments at all. The established plants get watered once a week or less. The hillside is on a sunny side of a canyon, about 850 feet above sea level. The hillside retains a lot of heat due to the DG and other rock outcroppings.

I have three Clinostigma savoryanum 5 gallons that I bought from Phil's two months ago. They have acclimated (I hope) and I wanted to plant them out on a small slope in DG. They would get sun most of the day.

Question: Should I amend with compost, compost and peat, or just plant them out. Most of my palms have been planted in well-mixed homemade compost and Dr. Earth fertilizer in the lower garden area, which is fairly moist and sheltered. The couple of palms I have in straight DG have been very slow to grow and are in full blazing sun.

Your experiences? Ideas?

Thanks!

David

[Hollywood Palms]

Pics of the area:

[MattyB]

Hi David, good to hear from you and to see some pics of the place. In my experience with DG and hot rocky hillsides is to ammend the backfill with 50% organic matter, 50% native DG, and then mulch the whole area around the plant very heavily to hold in moisture. Clinostigma, from what I understand, need to be watered less during the winter months, so the mulch will help keep the soil from drying out without having to water as much. Note: I have not planted any Clinostigma at my new place yet, so my experience with this particular species is none.

By the way, I think your home made compost is probably fine. Peat is a waste of money, I think, because it just breaks down so fast. Just get some organics in there and it'll be good.

[Kim]

I know you're in the south-facing hills, and probably have little to fear from winter, but having lost a couple of these palms myself, I suggest waiting til spring to plant. Maybe that's over-cautious, but I thought I'd pass on my experience to you. The DG will be good stuff, great drainage, very important with these palms. Like Matt said, mix in a little compost and you're set. I'd also toss in some slow-release fertilizer such as Dynamite or Osmocote-type granules (another good reason to wait for spring). Just my 2 cents.

[Walter John]

This is a no brainer, use compost, mulch heavily and water heavily. Looks a decent drainage spot too, as long as you mulch heavily and water heavily.

[MattyB]

Oh, upon reading your post title I see your "good or bad" question. Good! Very good! DG is great.

[Hollywood Palms]

Thanks for the , folks.

Kim-only winter damage I have had is from over-watering and putting a patio heater too close to a hibiscus. According to the Sunset Western Gardening Handbook, allegedly, I can plant anytime but the first two weeks of January. I think I'm gonna chance it.

Matty-I need to do a tour around my garden post. Maybe this weekend.

Thanks all.

David

[MattyB]

Yeah!!!

[surferjr]

Hi David, good to hear from you and to see some pics of the place. In my experience with DG and hot rocky hillsides is to ammend the backfill with 50% organic matter, 50% native DG, and then mulch the whole area around the plant very heavily to hold in moisture. Clinostigma, from what I understand, need to be watered less during the winter months, so the mulch will help keep the soil from drying out without having to water as much. Note: I have not planted any Clinostigma at my new place yet, so my experience with this particular species is none.

By the way, I think your home made compost is probably fine. Peat is a waste of money, I think, because it just breaks down so fast. Just get some organics in there and it'll be good.

MattyB NAILED IT!!

Mulch the top so the palm does not dry out....if not when you water it in the cold....she'll be history!

Clinos hate water in the cold months!

[Gtlevine]

My soil is identical, pure rocky hillside composed of D.G. I just dig a hole and throw in the palm, no amendments. On a yearly basis use mulch on the surface and fertilize two times a year with slow release. Experiments have shown that although D.G. appears similar to sand and you would think acts like sand and not retain nutrients, the opposite is actually true, D.G. holds nutrients very well, it is an excellant soil for planting tropical plants, especially in cooler climates because of the great drainage quality.

Gary

[MattyB]

Interesting, Gary, that you don't ammend the backfill. But I guess that if the drainage is great then the black humus (broken down compost) will work it's way down throughout the soil levels as it's watered over the years. Phil Bergman once told me that if he had to do his steeply terraced planters again he'd just use coarse sand in the planters and only add the mulch on top. That way he'd get no soil level drop but the organics would work their way down over time. Same idea as Gary's basically.

By the way, Surferjr has some great looking Clinos, and that's who told me not to water too much in winter. Plus he's a mulch nut too! I bet you'd wanna water just enough so that they don't go dry in the DG. I did this with Carpoxylon over winter and it worked great.

[doubravsky]

My soil is all DG too... and I started by amending a lot, but eventually just began digging the hole and going. The DG seems great... drains well, seems to hold nutrients well. I'd say dig and plant.

This spring, I got to dig up a couple 15 gallon Bismarckias, and I didn't have any potting soil handy, and I figured they'd croak anyways, so I just filled two 15 gallon pots with DG. Heavy as hell, but the palms actually seem to thrive on it. The two Bismarckias put out 4 new leaves each this summer, and recovered nicely from the shock.

[LJG]

David, the only thing I would add is maybe supplement the watering set up with some bubblers or drips. I have had a hard time watering step hillsides and retaining moisture. Water runs off or because it is DG, the water run right through the hill. So I water more on my hillside then on the flat areas.

[Matt in SD]

I water all my palms through the winter, including my Clinostigma savoryanum. Less than summer, but I never let anything dry out. Not had any problems. I would not plant any tropical palms this time of year in SoCal. It might survive the winter, but it's more likely to survive if you leave it in the pot. And it won't establish any quicker in the long run since I think the root growth through the winter will be minimal.

[elHoagie]

I also think it's too late in the year to plant, especially a more tropical palm. As far as the soil, I generally don't add anything to the planting hole. Unless the hole is huge the palm will have to grow into the native soil eventually, so why change a relatively small amount of soil? I'd rather mulch a huge area around the palm, that way all of the native soil will improve...

By the way, I have five Clinos I'll be planting in the spring. We'll have to compare our groves in a couple years.

[BS Man about Palms]

I planted my big Clino from Clark last Sunday. If it was smaller I would have probably waited until next spring. Heres hoping it makes it!

[Hollywood Palms]

Awww, darn it Jack...now, I'm thinking twice.

Well, I'm gonna do it. I've killed worse.

David

[Kim]

Why not employ a little risk arbitrage, Dave? You have 3 of them; plant 1 or 2 and hold back 1 or 2 until April. It doesn't make sense to risk all 3, and you'll gain useful information in the process.

[Walter John]

Why not employ a little risk arbitrage, Dave? You have 3 of them; plant 1 or 2 and hold back 1 or 2 until April. It doesn't make sense to risk all 3, and you'll gain useful information in the process.

Absolutely.

[Wai`anae Steve]

Pics of the area:

How do you keep all that "loose" looking ground from washing down hill when it rains????? Or does it pass water so fast that it won't wash down hill?

Any hill I have here and I have a lot although none over 20' I will/have terraced.

Wai`anae Steve

[Hollywood Palms]

Okay-so here are the results:

three palms planted-risking the future ridicule of Jack-and three ti cuttings from the big island of Hawai'i I grew.

Side views and overviews of the area. I mulched with cocoa hulls.

[Hollywood Palms]

Hey Steve,

I usually use soakers and/or drip. I also build small embankments. Sort of a multi-focused approach.

David

[BS Man about Palms]

Cool David!

Heres mine now planted about 2 weeks or so. I hope they ALL do well!

[Hollywood Palms]

Come on, el Nino!

[MattyB]

That looks great David! I should add that one of the reasons I ammend the backfill, is that I water by hand and this allows me to put a lot of water into the hole without it running off. I also like the idea of the area surrounding the trunk to be kept humid, but not burried under dirt, to prevent rot.