Question: My black eyed susans are out of control. If I pinch them when they first start to come up (like I do to my mums) will they come up smaller and less of them or do I just have to keep pulling them out year after year?
Answer: Pinching would not really keep them smaller, no. If they are crowded you would still need to thin them. Deadheading (removing the faded flowers) would also help limit them from spreading by reseeding themselves.
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