The leaves on my hibiscus plant on the deck are turning yellow. The soil test about 3 on the watering scale. Why are the leaves turning yellow?
Yellow Leaves on Hibiscus
Certified GKH Gardening Expert
There are several reasons this can happen, normally associated with stress of some kind. This article explains many of them and will help you decide which is likely for your plant: https://www.gardeningknowhow.com/ornamental/flowers/hibiscus/answers-to-what-causes-hibiscus-leaves-turning-yellow.htm
Do the yellow leaves stay supple and remain on the plant? If so, then overwatering or improper drainage could be the culprit. Although they are thirsty plants (even more when it's really hot) you really have to be careful with them and especially if they are potted in plastic pots (the water doesn't evaporate out as quickly as it does in ceramic). Generally in summer I water in their pots every second or third day (unless there is intervening rain) and then I water well - so there is about 1/4 inch of water on top of the soil. After watering check back in about 1/2 hr to ensure that there is no water still on top of the soil and the pot is draining out of the bottom. Hope this is helpful Good luck