Why have my cucumbers gone yellow when they aren't fully grown?

Answer 1

This is from Dr. Lynette Morgan:
"There are many causes of yellowing in cucumber plants--everything from major nutrient deficiencies and toxicities to pests such as spider mites that are small and difficult to see. There are also many diseases and viruses that can cause plant or fruit yellowing, so it’s almost impossible to guess what is causing your particular yellowing problem. However, here are a few possible causes.

* Nitrogen deficiency will cause older leaves to turn a uniform pale green to yellow. This condition spreads to younger leaves up the plant. Plant may be very stunted in severe deficiency conditions.
* Phosphorus deficiency will cause the oldest leaves at the base of the shoot to turn bright yellow and the leaves will die prematurely.
* Potassium deficiency in cucumber will cause yellowing and scorching of the older leaves. Symptoms begin at the margins of the leaf and spread between the veins out to the center.
* Magnesium deficiency causes yellowing of older leaves. The symptoms begin between the major veins, which retain a narrow green border. A light tan burn will develop in the yellow regions if the deficiency is severe.
* Manganese deficiency will cause the middle or upper leaves to take on a mottled pale-green or yellow appearance with green veins.
* Iron deficiency causes the youngest leaves to turn pale green or yellow with green veins. In severe cases the affected leaves may appear light yellow to white.
* Boron deficiency causes both leaf and fruit symptoms with the appearance of a broad yellow boarder at the margins of the oldest leaves. Fruit may become stunted, develop mottled yellow streaks, and produce corky markings.

Other problems that may cause yellowing include excess nitrogen, chloride toxicity, salinity damage, boron toxicity, herbicide damage, and phosphorus toxicity. Since there is such a wide range of potential nutritional problems that could cause yellowing, it might be a good idea to obtain a well-balanced nutrient mix and apply this to the plants to see if that helps.

Spider mites can also cause yellowing of the whole plant. This starts as a speckled appearance that gradually gets worse until the leaves and fruit become bronzed in appearance. Eventually, the tissue becomes brown and dried. Spider mites are very small and difficult to see, but if you look on the undersides of leaves for a very fine webbing and tiny orange dots, this pest is likely to be the problem.

Mites are difficult to control, but there are now predators that can be purchased for biological control. Also, soap and oil sprays can sometimes be effective if applied correctly.

There are also a few diseases that can cause yellowing, but often the symptoms of disease appear in isolated spots that rapidly spread causing other symptoms such as the appearance of fungal spores or wet rots.

There are also a number of viruses diseases that could cause these symptoms as well. Mosaic viruses can affect cucumbers. Cucumber mosaic virus results in older leaves turning yellow and drying up. New leaves sometimes wilt and die and there will be a slow decline of the plants. Some viruses are carried by insects such as aphids--others can be carried by infected seed. There aren’t any cures for virus-infected plants they are best removed and destroyed."
http://www.growingedge.com/community/archive/read.php3?c=PD&q=406
Good luck! Hope this helps.

Answer 2

Cucumber Turning Yellow

Answer 3

This Site Might Help You.

RE:
Why have my cucumbers gone yellow when they aren't fully grown?

Answer 4

Hi - It's possible that yhe plant is producing too many cucumbers, making it difficult for them all to get sufficient nutition from the soil/grow-bag. Cut off the growing tip of the plant when you have 5/6 cucumbers starting to form. You can also give them the same feed that you would use for tomatoes, this will help.

Answer 5

Darren, Are the cucumbers fruiting and shriveling up or the plant themselves? There are a few possibilities- poor soil, not enough light, not enough or too much water, and insects. To find out which it is you will have to experiment a little. Try more or less water. Add mature compost to your soil. pull up one plant by the roots and check for larvae or insects. A great way to find out is to call your local Master Gardener organization. These groups often have gardening hot-lines to call or centers to bring in plants to show to a real person. Search online for master gardener group in your area.

Answer 6

I am having the same problem. They aren t too wet, or too dry. They start out nice, pretty and green but soon turn yellow and are shaped like a ball or bell. It s very frustrating. Any advice will be appreciated!

Answer 7

This usualy happens when you have missed watering for a day or two also it could be that you are watering them with water direct from the tap you should leave the water overnight before useing.

Answer 8

Ever think that they may be yellow cucumbers? They do have them.

Answer 9

dont take this wrong, but i swear cucumbers are GREEN when they're fully grown cos thats what they look like when i buy em - green as ivy. only without the ivy cos if you eat ivy its poisonous.
but back to the point, i thought they're yellow and go green when ripe and ready???

Answer 10

usually water is the culprit when this happens,too much can cause root rot and cukes lying on wet ground can get this way too,especially when shaded by the leaves