Magnolia leaf mulch?

[Doelman]

I need to mulch my vegetable garden this weekend and I was thinking, why not use magnolia leaves? I have three large adult magnolias, plenty of leaves, I could mulch them up and spread them on the garden. Any thoughts?

 

[DirtMechanic]

Do not bother. Like a few other plants in the garden, magnolia has developed a chemical that retards attempts by other plants to grow. Plus the waxy tough leaves will be slow to degrade. I put them in the natural paths around the house to keep down weeds while getting crunched up.

 

[roadrunner]

I use all kinds of leaves for mulch and normally don't bother shredding them, especially the oak leaves, since they make a really nice looking mulch; however, I would run a lawn mower over Magnolia leaves, just to make them a little more compact as a mulch. The large size and waxiness causes them to be a poor mulch because the mulch pile has too many air pockets, which allows moisture to evaporate too fast.

I've also used the seed pods in the soil, I've found worms eating thru them, much like an apple, but they must be slightly buried into the soil.

 

[DirtMechanic]

I use all kinds of leaves for mulch and normally don't bother shredding them, especially the oak leaves, since they make a really nice looking mulch; however, I would run a lawn mower over Magnolia leaves, just to make them a little more compact as a mulch. The large size and waxiness causes them to be a poor mulch because the mulch pile has too many air pockets, which allows moisture to evaporate too fast.

I've also used the seed pods in the soil, I've found worms eating thru them, much like an apple, but they must be slightly buried into the soil.

Yep, everything will mulch down, but some things take a year or even more. And is it not amazing how much faster things move along with a little dirt on top. Just an inch or two of soil.

 

[Doelman]

Yeah I would definitely mulch it up before putting it on the garden beds.

Do not bother. Like a few other plants in the garden, magnolia has developed a chemical that retards attempts by other plants to grow. .

Where did you get this information from about the chemical in magnolia leaves? I've never heard of this before. I've trimmed up all my magnolias and I'm constantly having to weed wack plants underneath them.

 

[DirtMechanic]

The chemicals are sesquiterpene lactones. Here is a link to Mr Smarty Plants :
https://www.wildflower.org/expert/show.php?id=5368

I understand that there are some plants that will make it, but its a case of them being non-native or different somehow in ways that are past my pay grade. Mostly I learned from fighting my magnolia.

 

[Mystic Moon Tree]

My magnolia tree's leaves kill a lot of plants under them. Plants that survive & thrive when the leaves aren't too thick: wisteria, blackberry, lemon balm, rose, lambs ear, oak. Violet, sweet pea, & holly hock will survive on the fringe of the leaf litter.

 

[Marck]

By all means do use your Magnolia leaves somewhere as mulch or compost material, just place them correctly. Alleolopathy, or the inhibitory effects of plant chemicals on the growth of other plants is a real phenomenon in nature, but its effects in garden situations is quite over-stated. Most of the measurable effect, if any, is on seedling survival. Many people garden successfully in shade or part-sun under Magnolia trees, Eucalyptus trees, and even beneath dreaded Walnuts (Juglans spp.), which have become the poster children of allelopathic over-reaction.

It is true, the evergreen leaves of Bull Bay (Magnolia grandiflora) and other evergreen species will be slow to decay. Not the best for vegetable bed mulch, but ideal for mulching woody plant beds and garden paths, including the paths around the vegetable bed. The leaves of deciduous Magnolia will decay much quicker.