More Bay Laurel Problems
Answered by: Inge Poot
Question from; Lanette Spranzo

I have a bay tree in a large pot that I received as a little seedling (or cutting, I should say) in 1980 yes, my Laurus nobilus is twenty-five years old this year! I have trimmed the plant -- several times to its present size of about 45" wide and as tall at that. Oh, and another problem is that I moved the plant in June into an unheated breezeway that gets a bit damp. As winter set in, I moved into my office here, which is about 55 degrees or warmer most of the time. Here are the signs of decreasing wellness that my bay tree displays lately.

Even in the location this plant liked best - one in which it received gentle morning sunlight and a shielded southern exposure, I noticed a puffy bright yellow fungus-like growth on the top of the soil. I used to scoop out what I could see of this substance, but it would slowly grow back. In its new location this past summer, which is cooler, and more humid, the fungus grew more abundantly. Someone suggested that I spread crushed egg shells over the top of the soil, so. I cracked open many eggs and used them -- though they were unsightly sitting there under this pretty bay tree! The yellow puffy growth did abate, but was not completely deterred. Someone else suggested I spread limestone over the top of the soil -- which I did. Again, ugly but apparently effective.

The fungus that grows in your bay laurel pot likes acid conditions. By liming the soil -- slowly with egg shells and fast with ground up lime -- you changed the pH to a higher one that does not agree with the fungus -- and presto -- it declines.

Another problem: there are black spots on the leaves, and small brown dots on the underside of an increasing number of leaves, and I notice that when I dry these leaves they curl and discolor. Are these still safe to use as culinary herbs - I like to use them in soups and stews.

They are still safe to use, but may be more bitter than unblemished leaves. The cooking will kill any fungi or bacteria, but won’t do anything for the flavour. Check this out, before using them!

One other embarrassing problem. Tiny fleas are popping out of the soil and alighting on the leaves, and flying all around the house..... Maybe the rotting eggshells gave birth to them? Also a white mold-like substance - not pervasive but definitely there - at junctures around trunk and a few adjacent branches and stems.

The remaining egg in the egg shells could have given food for any number of creatures, but the raised pH could also be the culprit, that is favouring the insects’ growth.

I think I need to re-pot the plant and would like to ask that if I do, should I treat the soil with insecticide? Should I try to scrape out as much of those old eggshells as possible - and do you think this is where the little fleas are breeding? Also - is that puffy fungus anything to worry about?

Repotting is very advised. Wash the roots well also to remove as much of the fungal material as possible and all of the eggs of the flea-like insects. I think the latter may be spring-tails, harmless for most plants, but unsightly. Do not use an insecticide on the soil, because you plan to eat the leaves of the tree. More frequent repotting with careful washing of roots and pot should control the fungus problem.

Lastly, but probably most importantly, keep the plant a little drier to control all of your problems. Wait to rewater until at least 2 cm of the top of the soil is dry.

Back to Growing Herbs | Q & A Index

Copyright © 1997-2014 Otto Richter and Sons Limited. All rights reserved.