Expert: C.L. Fornari - 7/27/2006

Question
Some of my marigolds have stopped flowering and there are only the healthy (looking) leaves left with no but stems.  I've been cutting off the wilted flower as I've seen them about 1 inch below bud.  I'm in a large deer area and I know some of the flowers have been pulled up by the roots and are gone but these others have just stopped flowering and those that are seem to be getting less and less flowers.  Could this be slugs?
Now the Marigolds I have in the planters are getting all of a sudden very long flower stems that have buds - but seem not to be flowering before wilting - no deer or rabbits here.  The plants and leaves on all of these have gotten very large and green but way underneath I'm seeing yellowing.
I am a first time gardener - trying not to be discouraged...  

Answer
Caryn,
If the flowers aren't being eaten off by the deer, the problem might be not enough sun.  Are the plants getting at least 6 hours of sun a day, including the noon hour when the sun is the strongest?  This is what marigolds like.  They also do well with slightly less fertilizer than most annuals, and water only after letting them go a bit dry, but not to the point of wilting.  Many annuals like a fertilizer that has higher nitrogen, but for marigolds, a higher level of nitrogen (when the first number on a fertilzer package is higher or the same as the others) encourages too much foliage.

Slugs eat foliage not the flowers only, so I doubt that this is the problem.  The yellowing leaves are not really a concern if the upper part of the plant is doing well - all plants shed their lower leaves as the top grows, because the lower leaves end up shaded by those above, and the leaves are for photosynthesis, so if no light is getting to them the plant sheds them in favor of putting all resources to the ones that are doing the job of creating food.

It's useful to know that if only the older leaves are yellowing, it may not be a problem, but if a plant has gotten too dry it will also drop lower leaves faster, again, trying to put all resources to the top, new growth.  If a plant is turning yellow all over, however, this is either root rot (too much moisture) or an iron or nitrogen deficiency...probably not your problem.

Plants are sort of like children....each has it's own needs and personality, and part of the fun of gardening is learning what every plant needs to do well.  And sometimes the symptoms you see are the result of a plant responding to several situations....the combination of not enough sun, slightly too much fertilizer, and a nibbling deer, for example.

Let me know if this doesn't answer your question and we can take another stab at it.
C.L.