What causes this?

eastwood2007 · Post by **eastwood2007** » Apr 18, 2007 10:34 am

What causes this type of leaf damage? Many of my yellowish hostas have this right now?

renaldo75 · Post by **renaldo75** » Apr 18, 2007 10:53 am

The cold temps did it. Unless they're really bad, I'd just leave them for now. The ones with less damage should start looking better in a few weeks.

eastwood2007 · Post by **eastwood2007** » Apr 18, 2007 10:57 am

Hmmm...well, this one was in the greenhouse, and only came out while the temps were above 40 overnight, and even my babies that have never been exposed to anything below 50 have it, too?

renaldo75 · Post by **renaldo75** » Apr 18, 2007 11:14 am

Not sure what to tell you then, but I'd still bet on the cold. Even though it didn't get real cold in the greenhouse.

This is what a lot of my hostas that didn't turn to mush looked like a couple of years ago. They didn't look good after a week so I cut all but 4 [that I missed] back. But eventually even the damaged leaves on those 4 looked pretty good again. So I decided after seeing how they rebounded that I hadn't really needed to cut back the 100's that I had...

Hindsight and all that good stuff.

hummingbird · Post by **hummingbird** » Apr 18, 2007 11:28 am

Char some sun, or winds can do this very easily if the plants aren't quite hardened off yet; especially from the greenhouse since they're rather tender in there, this may be the case here. However it's superficial damage at least.

Hank Zumach · Post by **Hank Zumach** » Apr 18, 2007 11:37 am

Hi--Even having dew or other moisture on the leaves, along with some wind, can cause this if the temps are low.

Mortko · Post by **Mortko** » Apr 18, 2007 12:11 pm

Hi Charla,

This is caused by low humidity in your greenhouse. Similar to spring desiccation burn we see in the gold leafed sieboldianas, but is is common with many gold hostas. In the spring, it's not uncommon to be 80 degrees in the greenhouse, while the incoming ventilation air still has dewpoint is in the 30's. Do you recall seeing the fogging unit hanging from the ceiling in our greenhouse? That was our solution.

Rob

DBoweMD · Post by **DBoweMD** » Apr 19, 2007 8:48 am

Hey welcome to the forum Rob! I see that was post number 1.
Thanks for your excellent explanation. It makes total sense.