Answer: When you say filled with 6 inches of compost, does that mean compost only, without soil? Plants need a soil that is rich in organic matter such as compost, but compost alone doesn't provide all the required nutrients. All of those herbs enjoy full sun, so that is good. However, they shouldn't need to be watered every night. Water slowly and deeply to moisten all of the soil. Then let it just barely dry out between waterings. To maintain soil moisture, layer 2-3 inches of mulch on top of the soil. This also helps moderate soil temperatures. Most herbs don't need extra fertilizer if the soil is rich and well-draining (they don't like wet feet). I hope this info helps.
Q&A Library Searching Tips