15 replies to this topic

[tank]

Knowing that this was an issue, but thinking that it wasn't THAT big of an issue, I planted some saw palmettos, a couple sable minors, other native plants including Lyonia ferruginea, a couple sandhill vaccinium species, and a Macrozamia communis under a large magnolia. The magnolia is in a very sandy dry area and this has given it a more narrow and open form leading to some really nice diffused lighting underneath it which I was trying to take advantage of. Needless to say after a year, everything under the tree is struggling or dead. Its kinda cool as you can see a very distinct "ring of death" around the tree.

[fastfeat]

RE: "ring of death" around the tree.

Seems to have extended all the way to SoCal, 'cause I can't see the pic...

[kahili]

Why do you think that they died, Tank? I am guessing that the roots of the Magnolia sucked up all the water? Or too much shade? This is reminding me to start checking for blooms on mine-a few blooms in a room are really aromatic.

[rozpalm]

Knowing that this was an issue, but thinking that it wasn't THAT big of an issue, I planted some saw palmettos, a couple sable minors, other native plants including Lyonia ferruginea, a couple sandhill vaccinium species, and a Macrozamia communis under a large magnolia. The magnolia is in a very sandy dry area and this has given it a more narrow and open form leading to some really nice diffused lighting underneath it which I was trying to take advantage of. Needless to say after a year, everything under the tree is struggling or dead. Its kinda cool as you can see a very distinct "ring of death" around the tree.

I have found that ginger has no problem growing under them but little else. I had a majesty palm planted under it and within two years it killed the thing. It just collapsed. What is strange is that I have other things near the tree, but not under it and they seem to do fine.

[DoomsDave]

Some plants poison the soil and kill other plants near them.

Walnuts, if my memory serves, are one plant that does that.

[Eric in Orlando]

The worst are Camphor Trees, very hard to grow other plants under them. The only thing that seems to grow well under camphor trees are camphor seedlings.

[santoury]

That is very interesting - I had no idea Magnolias did that - they are a popular tree here - and now that you mention it, they typically don't have anything planted under them.
Walnuts, or at least the Black, is well known for this.
Anything growing under Pine trees need to enjoy acidic soil, but that's only because of the needles.

[Mandrew968]

Anyone know if Delinox regia has these properties? I have heard that it does, by a few people, but have seen no evidence of such claims...

[tank]

Offending magnolia

[fastfeat]

Anyone know if Delinox regia has these properties? I have heard that it does, by a few people, but have seen no evidence of such claims...

I don't believe so. I don't think there are aromatic compounds in their foliage that subdue growth, unlike trees in Lauraceae, Myrtaceae, Magnoliaceae, Juglandaceae, Anacardiaceae, others.

Strong surface roots compete for space under Delonix, but they're relatively easy to grow plants, including turf, underneath, with sufficient irrigation.

[Mandrew968]

Anyone know if Delinox regia has these properties? I have heard that it does, by a few people, but have seen no evidence of such claims...

I don't believe so. I don't think there are aromatic compounds in their foliage that subdue growth, unlike trees in Lauraceae, Myrtaceae, Magnoliaceae, Juglandaceae, Anacardiaceae, others.

Strong surface roots compete for space under Delonix, but they're relatively easy to grow plants, including turf, underneath, with sufficient irrigation.

Thanks for the info and accurate spelling. So the leaf litter can subdue growth?

[tank]

The worst are Camphor Trees, very hard to grow other plants under them. The only thing that seems to grow well under camphor trees are camphor seedlings.

Eric,
We had a MASSIVE camphor cut down at my old house, basically eight trees fuzed together into this massive beast the tree guys dubbed "the octopus". Each trunk was over 30" in diameter. After two stump grindings, two because they lost the trunk in the 4' tall pile of shavings on the first go round, we had a mountain of aromatic mulch. Had the neighbors commenting/complaining for a week about the smell, asthma attacks, shortness of breath, etc. I had the great idea of mulching all of my plant beds at one of my rental houses with the camphor mulch. Bad idea. Killed or set back most of the plants that got mulched. Boxwoods, gardinias, privits, all of it pretty standard cheap landscaping. It was crazy. Most dropped their leaves within a couple weeks and all the new growth that happened to appear for the next couple of months was stunted and funked up looking.
Nasty stuff.
Only good thing about camphor is that the wood is really nice when milled, has a beautiful golden hue when finished. Wood is often used as a veneer.

[fastfeat]

here

Anyone know if Delinox regia has these properties? I have heard that it does, by a few people, but have seen no evidence of such claims...

I don't believe so. I don't think there are aromatic compounds in their foliage that subdue growth, unlike trees in Lauraceae, Myrtaceae, Magnoliaceae, Juglandaceae, Anacardiaceae, others.

Strong surface roots compete for space under Delonix, but they're relatively easy to grow plants, including turf, underneath, with sufficient irrigation.

Thanks for the info and accurate spelling. So the leaf litter can subdue growth?

It's compounds in the foliage of certain trees that causes allelopathy, though strong surface roots competing for nutrients/water, dense shade by foliar canopy, and sheer volume of leaf litter can inhibit growth and prevent seed germination under trees that don't have allelopathic compounds. Usually under Delonix (well-grown ones anyway), it's often just too dark for many sun-loving plants. But under thinner-canopied trees (had a couple at my Miami Springs house), St Augustine grew fine. (I actually used to have many Delonix seedlings germinating in the turf, since I just mowed the pods with the grass.)

More on allelopathy here and here.

[fastfeat]

The worst are Camphor Trees, very hard to grow other plants under them. The only thing that seems to grow well under camphor trees are camphor seedlings.

Eric,
We had a MASSIVE camphor cut down at my old house, basically eight trees fuzed together into this massive beast the tree guys dubbed "the octopus". Each trunk was over 30" in diameter. After two stump grindings, two because they lost the trunk in the 4' tall pile of shavings on the first go round, we had a mountain of aromatic mulch. Had the neighbors commenting/complaining for a week about the smell, asthma attacks, shortness of breath, etc. I had the great idea of mulching all of my plant beds at one of my rental houses with the camphor mulch. Bad idea. Killed or set back most of the plants that got mulched. Boxwoods, gardinias, privits, all of it pretty standard cheap landscaping. It was crazy. Most dropped their leaves within a couple weeks and all the new growth that happened to appear for the next couple of months was stunted and funked up looking.
Nasty stuff.
Only good thing about camphor is that the wood is really nice when milled, has a beautiful golden hue when finished. Wood is often used as a veneer.

OTOH, excellent for mulching in areas you want to minimize weed growth. At least until the camphor seedlings start to germinate...

[Mandrew968]

Thanks for the information!

[ariscott]

I grow all sorts of stuff under delonix. I find that they provide just the perfect dapple lights for all those tender tropical stuff. And they grow SO FAST

Regards, Ari