I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
Yellowing of inner and lower leaves can be due to a number of things. There is a natural loss of older leaves periodically especially as new growth emerges or as the plant is in a major bloom cycle. Dry soil or soggy soil conditions for a period of time may also be involved in yellowing and drop of older leaves. Finally if the bush is just not that green overall and older leaves are yellowing, a lack of nitrogen could be to blame.
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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