Is this leaf spot? (on courgette leaves)

My wife has a few very healthy looking courgette plants that are currently inside on a west facing window sill - a few days ago a couple of leaves developed what I think is leaf spot and so were cut off.

Now two other leaves (on other courgette plants) have it.

I've cut off one leaf and taken a photo - see below.


Is this leaf spot?

If so, is bicarb of soda in a spray solution a good treatment for it? I'd like to avoid pesticides if possible (but will use it if necessary) but I also don't want to have to keep cutting off affected leaves.

Thanks

 

I dont think its anything to worry about.

 

Really? Are you 100% sure? It was a lot worse on one of the other leaves which was removed a few days ago (so I am assuming that this one would have developed too).

 

No I'm not 100% sure, but it looks like more a problem down to growing conditions.
The plants should be hardening off now.

Leaves get all kinds of blemishes etc. during the growing season it doesn't automatically mean disease,or pest.

 

Okay, thanks.

So time to start to hardening them off then.

 

Could it be Downey Mildew or Powdery Mildew?

Here's a link to the original photo which can of course be enlarged using the magnifying tool at the top right corner of the image:

http://s59.photobucket.com/user/Dalek99999/media/P5210973.jpg.html?o=0

 

Some extra info from my wife - as the courgette seedlings are in a window some of the leaves WERE getting damp due to them touching the window pane and condensation forming overnight.

So does that mean that the affected leaves have powdery mildew?


Additionally, here's a curious question - during the hardening off process, if they get wet outside (from rain) and then brought inside, is that likely to be a problem? Or do we need to pat them dry with kitchen paper first?

 

You need to remember that these are outdoor plants,that can take the gentle blows that Nature throws at them. No need to "pat dry" if they get wet outside. Once they are planted out, they will be getting wet leaves at least once a day - it's called dew! What might have caused a little stress is the hot/cold extremes of leaves indoors against glass. I can't see on your profile where you are, but in the Midlands, we used to plant the courgettes out at the beginning of June, having been hardened off (outside unless v cold overnight, with a little shelter from a building) for the 2-3 weeks previously. Mine are planted out already. They had had a soft cloche on (we've had night temps down to 5-6, and they are in an exposed site) but I removed that yesterday, so that they could enjoy the rain we've had overnight and today. So they had their first thunderstorm at about 4am this morning. I'm not about to run out and dry their leaves!!

Edited to add:
If the spots were almost silver in colour, it could be the natural colour pattern of the leaves. Courgettes do not have uniform green leaves.

 

Thanks very much.

As for my "pat dry" suggestion (which admittedly seems a bit daft!) - that was only in relation to the early hardening off process and them being outside for a few hours in the rain then brought inside for more hours (and was suggested for mildew prevention).

 

A little air-flow around the leaves would help them dry quite quickly, if brought back in damp. The leaves are hairy, so manually drying them would probably cause more problems than a spot or two of mildew, which would be washed away in the next shower...

 

Good point, thanks.