I know there's tons of information about yellowing leaves on the internet, but online so far leads to answers like: 'You're either watering too much or to little'. I'm thinking, so that's it, now I know! Mine is in a container on the deck. For the size container it was spreading well, and have a couple of pickle sized cucumbers so far. A few days ago the leaves looked really dry, so I watered more than usual. They seemed to recover in that respect, but of course still yellow.

Based on that maybe watering too little? Unfortunately this area was just officially declared to be in a moderate drought. I may have some fertilizer on hand, maybe will try a little of that. Next to it, in a larger container is a cherry tomato plant. While the leaves don't look perfect, they're not yelow.

Any idea what could be the trouble? Maybe there are too many variables with each situation to provide a general answer.

 

yellow leaves do not typically ever go back to being green they just die off are you can cut them off, so if it was a watering issue and you continue to get more after correcting the issue perhaps its something else like nitrogen deficiency.

 

I did read a lack of nitrogen can cause it too. The cucumber plant leaves in the actual ground garden were good and green, but they got eaten by something. I made the fence higher, which probably won't help which is why I wanted to try growing them on the deck where they're protected pretty well,

i am surprised how much the plant has grown and spread from a not very big container. If it just holds up with the yellow leaves.

 

lots of possible causes for yellow leaves if its only a few I probably would not worry to much about it, but nitrogen deficiency usually hits the oldest leaves first if you did have to fertilize I would use a balanced npk ratio as to much nitrogen could inhibit new flowers and cucumbers from developing.

 

Ok, sounds like it needs to be a good balance. Now that I think of it, it's happened other years as well. Didn't use any fertilizer, I have some on hand though, Just used soil from the yard and a bit of wood stove ash. Maybe next year I'll buy some garden soil.

 

most vegetable plants will benefit from fertilizer not sure what type of success you have had in past years but you may want to try using it more and I think you will notice a big difference.

 

It's hard to say without seeing a photo but cucumber can be huge plants and can put a hurt on the small amount of soil in a pot. I would not be surprised if the plant isn't starved (needs fertilizing). This often shows as the oldest leaves near the base of the plant yellow. The new growth at the top is stealing nutrients from the old leaves at the bottom.

Watering is always an issue in a pot. In July and August our veggies in pots need watering twice a day, and that is with additional water absorbing crystals added to the soil.

 

I noticed the leaves were starting to wilt again today so I watered a few times. I do have some fertilizer on hand, I will read the directions and apply some today. Not the best choice for a pot as you can see - next year if I do this I'll probably use a 5 gallon bucket.

Picked a couple ripe cherry tomatoes, I see others just starting to ripen. From what I can tell, the tomato plant looks relatively normal. As mentioned. watering twice a day would be ideal. I will do that tomorrow before heading to work and after work. On top of the drought, we've got a heat wave predicted for at least 7 days.

Thanks for the posts/information so far.

 

The dark deck boards are absorbing heat and cooking your plants.

 

The best way to tell if your pants need watering is to stick your finger in the dirt. If it feels damp don't water. I use Miracle Gro All Purpose Plant Food for feeding my potted tomatoes and peppers. I feed once a week. My guess is that the plants may be nitrogen starved and the nutrients in the pots are depleted. Because our summer has been so dry I water twice a day. I also have bases to get the plants off the hot deck.

 

I had some Miracle Grow All Purpose Plant Food as well on hand, measured accordingly into a gallon of water which I'll start using. Will keep the moisture test in mind. I never thought of the deck boards heating up the containers. I'll need to raise them.

 

The dark plastic pot (and deck boards) are absorbing sun and heating up the soil. Get a meat thermometer and see. Soil should be around 70. If you water a plant, mid day, while the leafs are wilting......that is a bad thing. Wait until dusk. Are there green veins in the yellow leaf ?

 

Last evening I got the pots raised up a bit. Was going to do he moisture test, but surprisingly got some much needed rain.

 

Don't know if just a coincidence or it has to do with fertilizer - after mixing an amount of Miracle Grow in a watering container the leaves seem a little less yellow. One day when coming home from work on a hot day the leaves were somewhat wilted. Watered the pot well and even after a few hours the leaves looked better.