( Black leg or Black Rot )
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Stem is almost hallow
Rotten to the core
End is Black and hallow
Plumeria Cutting x section
Tissue is totally rotten
Stem Rot is a disease that causes the decaying of the inner layers of the Plumeria. The plumeria stem becomes soft and squishy as the inside rots away. Stem rot moves very quickly and is almost always fatal to cuttings. Stem Rot usually occurs while trying to root cuttings or during winter storage. Cool temperatures and wet soil are the favorite playground for Stem Rot. Rooting and newly rooted plumerias during their first overwintering are at highest risk for developing stem rot. Once a Plumeria has survived it's first winter, Stem Rot is usually not a problem.
Plumeria Cuttings : Infected cuttings typically fail to root. Instead they develop rot that gradually moves up the stem. Leaf wilt and leaf spotting may be evident. The rotted stem eventually becomes shriveled, turns dull dark brown to black in color, and falls over in its pot.
Mature Plumerias : Although rare, mature plants can lose a branch or two from stem rot and/or freeze damage. Freeze damage looks almost the same as Stem Rot. In either case, with mature plumeria just cut off the affected areas and a mature plumeria will bounce right back with new branches and leaves.
*** Because Stem Rot is virtually untreatable,
How to Avoid Stem Rot on Plumerias
Note: There is no effective treatment for stem rot once it becomes established.
1. Be Sanitary. Keep the growing area
clean and free of fallen leaves.
2. Dust cuttings with fungicide before potting in media.
3. Always use "rooting hormone With Fungicide" in it.
4. Root Cuttings in individual sterilized
5. Do Not use Livestock manure in the rooting soil
6. Use a fast draining media like Perlite
for rooting cuttings.
7. Do Not overwater rooting cuttings... when it doubt, wait a week.
8. Repeat .. Do Not overwater rooting cuttings.
the growing season and winter storage check your plants
During winter storage keep you plants as warm as possible,
11. Try to keep the Plumeria growing with grow lights during it's first winter.
12. At first sign of Stem Rot treat it with liquid Fungicide and try to keep the soil dry.
13. If all else fails...take a cutting from the plant at any location you can get clean healthy wood, and try to root it.
If you are having reoccurring problems with Stem Rot,
Plumeria 101 / Michael Anders