Growing cucumbers outdoors is not that easy, because the sensitive vegetable is not only popular with snails, but is also susceptible to leaf diseases. You can find out why cucumber leaves turn brown and what you can do about it in this guide.
Why do the leaves of outdoor cucumbers turn brown?
Spider mites, nutrient deficiencyorWilt diseases are the most common causes of brown leaves on outdoor cucumbers. In very hot summers, the cucumbers react to the high temperatures by turning the leaves brown.
How do I recognize spider mites on outdoor cucumbers?
As a result of the pests' sucking activity,yelloworbrown spots initially appear on the leaves of outdoor cucumbers. Theseflow together,until the leaf is completely dry. If you look closely at the plants, you can see fine webs.
The pests can also become a problem outdoors, especially in hot summers.
How can I combat spider mites on outdoor cucumbers?
Since spider mites do not like high humidity,sprayFirst spray the cucumbers with thesoft jetof thegarden hoseoff.
- Dissolve a tablespoon of curd soap in a liter of water and spray the cucumbers with it.
- Alternatively, a rapeseed oil-water mixture can also be used: Mix one part rapeseed oil with four parts water and a little dishwashing liquid.
- Predator midges and gall midges are the natural opponents of spider mites. The animals can be bought from specialist retailers and released on the cucumbers.
How do I know that nutrient deficiency is the cause?
Due to the lack of nutrients, the ability to photosynthesize decreases and theleavesbecome increasinglylighter,until theyfinally brownwill be. In outdoor cucumbers, a nutrient deficiency usually only occurs when they are already bearing a lot of fruit.
- Work manure or compost into the soil before planting the outdoor cucumbers.
- Additionally mix the substrate with a good long-term fertilizer, such as horn shavings.
- From fruit formation, you should fertilize the outdoor cucumbers with nettle manure every two weeks.
How do wilt diseases manifest themselves and how are they combated?
Wilt diseases in outdoor cucumbers can be recognized by thewiltingand thebrowningof the leaves by thefungal network,that stretches over thestems. Wilting can be triggered by cold irrigation water, which cools the soil too much on warm days.
Another possible cause is fungi that penetrate the cucumbers' ducts and clog them. The disturbed water transport causes the leaves to dry out and turn brown. In this case, the only solution is to remove the infected plants and dispose of them with household waste.
How can I prevent heat damage?
- Young plantsin springcarefullyget used to the changed conditions in theoutdoors.
- Shade the cucumber plants on hot summer days.
- Water at least twice a day with lukewarm water.
Tip
Only cut off cucumber leaves close to the ground
In order to keep fungal spores and pathogens away, it makes sense to remove the lowest leaves from outdoor cucumbers. Since all interfaces are open entry points for pathogens, the plants should be carefully observed after this care measure. You should also cut out brown leaves to protect against diseases.
