rather 'gracious' cucumbers, the straight one is 50 cm long

Hi Hildadorissen, I have grown Cucumbers in my greenhouse for the first time this year. I have already taken one off and very good it was too. I notice that my leaves are like yours in this photo. Is this normal?
Thanks
Polly

Hi Polly,

It is probably a fungus, that turns the leaves yellowish brown, and brittle later on. We have had it too each year, but usually later on in summer when we 've already had enough cucumbers by then. There are products you can use, we try to avoid this as much as we can.
Do you also grow tomatoes there? Last year we had a lot of whiteflies on our tomatoes and cucumbers. I think you can try to prevent this by keeping them well watered, but try to keep the leaves dry. It looks to me that if any of my plants stay a bit dry for a couple of days, they get whitefly very quickly (for instance on my fuchsias, basil plants,...). I read a lot about it, and sometimes people contradict each other. For instance, a tip is to hose the plants with a strong hose, while others say to avoid too much moisture on the soil, especially in the evening.
I've looked up a lot for you, here are a few tips:
"PHYSICAL AND CULTURAL CONTROLS:
If you had clouds of whiteflies on your tomatoes or beans in the previous year, then acting early in the spring is your best bet to control this pest! Useful strategies include:

Vacuuming in the early morning when whiteflies are cold and slow moving can remove many of the adults before they have a chance to lay many eggs. After vacuuming, empty the vacuum bag into a plastic bag and put in the freezer for 24 hours.
Hang sticky yellow traps above the plants, at the beginning of the season to detect an invasion early. Tapping the plants with a stick will cause the whitefly to fly up and onto the traps. Whiteflies are strongly attracted to the colour yellow, so you really shouldn't wear yellow clothing around whiteflies or you may carry them from plant to plant.
Physical barriers such as floating row covers or mosquito netting work very well for early-season protection.
Handpick older leaves to remove young whitefly stages.
Avoid using a lot of nitrogen fertilizer, including manures, as succulent growth will increase whitefly populations. You may need to check your phosphorus and magnesium levels, as deficiencies in these are believed to contribute to whitefly infestations."
Philip says you should check your magnesium levels.
It is a real nuisance, for last year we lost all our tomato and cucumber plants at a later stage, because of these whiteflies. They were completely covered with a black substance.
Those sticky yellow traps seem to me worthwhile, perhaps we'll buy some soon.
Just look out if you've perhaps got whitefly under the leaves.
My advice for tomatoes and cucumbers: a lot of water every day, a lot of feed now and then. Success!