HELP! My Herb Plants Turning Yellow?

Question

I have an herb garden growing in pots outdoors. They were started from good seed and planted in a top grade potting soil. They have plenty of direct sun or I can drag them in the shade. Cilantro, basil and a few others. The plants were thriving, very green in the beginning. Due to a hot summer and a few heat waves, I had to water the plants daily or they would droop. All of a sudden, I noticed the cilantro getting yellowish speckles and then loosing their intense green color. I did put a few drops of Miracle Grow in the water can from time to time. I want to bring the plants back to where they were. They aren't dying, just not getting as green as they should be. What am I doing wrong and what do I need to do to get them healthy again?

Answer 1

If they are just turning yellow that is one of the first signs of too much water. If you got into the habit of watering every day when it was hot and are still doing it you're probably overwatering. And don't water them close to the end of the day. If the foliage is wet when the sun goes down fungal diseases may get a start. Most herbs like the sun.

The speckle look could be significant. If a plant gets spider mites or thrips they are usually on the bottom of the leaves. When they puncture the leaf to suck out some sap that can make a tiny spot on the top of the leaf. Check the bottoms of the leaves carefully with a magnifying glass because both of those pests are smaller that the period at the end of a sentence. If you do see any tiny bugs they are probably causing the speckling. You can kill them with insecticidal soap--it has no poison so you can use it on herbs. It works by coating the insects and suffocating them. You can also use a horticultural oil (they kill the same way) but they take a little more water to wash them off.