Showy Primrose -Not So Showy Now

I have had years of growing - and at times enjoying ( at at times fighting) this Missouri Native.

This perennial plant is useful only when correctly sited. Although it has a long blooming period and pretty pink flowers, it can become an nusiance in many situations. I enjoy many of the less agressive members of this species that have allowed me to be more energy efficeint!

While in flower, the foliage breaks out in a rash of blochy spots that turn red, run together and eventually offer a spoiled worn foliage look that looks tattered the rest of the season.

It happens annually, regardless of hot or cool weather, fungicide applications and moisture levels. The foliage "ripens", colors (like it is fall) gets a tattered look with spotting and browning.

Since I do not use chemical controls, I have agressivly cut back all the foliage and done extreme clean up ( making sure as much folage is removed and not left to lay on the ground) It usually resprouts, with slightly cleaner foliage. The plants continue to flower annually and return relaibly without any obvious loss. As a matter of fact- I would have been grateful for some decline as this colonizer is tough!

(Watch for "Tough Enough" blog entry about agressive Missouri Natives!)

Here I have listed just a few foliar diseases that affect this plant:

Cucumber mosaic virus
Sclerotinia blight
Phytophthora & Cylindrocladium diebacks
Leaf spots of several sorts attack but shouldn't be serious.

Infected leaves can be picked off.

Powdery mildew coats the leaves with a white powdery growth.
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