My lupins grow well at the beginning of every season but then begin to wilt and basically disappear. Plants all around them seem un affected. Ive searched online and the best match seems to be phytophthora or root root, it is activated by warmer temperatures, which might explain why they do well until mid June.
Is there anything else you can think of? Are there any remedies I can try- the same result from two plants about 8 feet apart
Any ideas would be welcome
Thank you for contacting Toronto Master Gardeners with your question.
You have done a good research on the problem of your lupines and found the best match. Phytophthora Root Rot of lupins causes sudden wilting and death of lupine plants within days during pod filling. The fungus survives in the soil, becomes established and develops in poorly drained soils when the soil temperature is above 15C . Unfortunately, to eradicate the disease you should remove all your lupines and plant other flowers. As lupines are members of the pea or legume family (fabaceae), you would avoid all plants from this family as well.
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