have a full southern exposure and have grown cucs, peppers and tomatoes before in the ground
I had minimal success growing in containers.

The problem you are encountering is due, I believe, to not having fully understood the difference between growing in the earth and growing in containers.

Growing in the earth means 90% of everything the plants need is provided by what they are growing in. Growing in containers means 100% of what the plants need is provided by you.

Growing in containers means *you* must provide oxygen, ample space for root growth, nutrients and water.

Providing oxygen means not using dirt, but a light weight potting soil that is 'packed' much more loosely than any soil.

Ample space means an appropriate sized container (more on this later).

Ample nutrients means using a complete, water soluble fertilizer frequently (no less than every other week)

Ample water means watering every day when it is hot and the plants large. Never allowing the potting mix to dry out completely with the veggies you are growing or they will suffer severely. I have one large container [10 gallon], 2 five gallon and one rectangular container that is about 6 inches wide x 3 ft long by 6 inches deep.

I would put the cucumber (no more than 2 vines) in the 10 gallon container. The tomatos in the five gallon buckets and the peppers in the 6" deep trough.

The cucumbers will need a lot of water, the tomatos can't be allowed to have their potting mix dry out or you will get blossom end rot. The peppers shouldn't dry out either, but will be more tolerant of low moisture.

The cukes will need much fertilizer to do well, the tomatos a more moderate (but regular amount) and the peppers the least, but still a regular fertilizing program.

If you are reading what I have written and it makes no sense to you at this point in time then here is what I suggest.

Purchase Miracle Grow potting mix (not soil) for all containers. I recommend MG brand potting mix only because it is decent and widely available. I won't recommend anything on this forum if it isn't widely available. Ensure that every container has at least one decent sized hole in the bottom for excess water to drain.

Buy a water soluble fertilizer (I like DynaGrow, but Miracle Grow fertilizer is OK). Use it at 1/10th recommended strength every time you water the plants.

For good measure buy some Osmocote or similar and mix according to instructions with the potting mix before planting.

Water such that the potting mix never gets dried out.

You will have large, healthy, high producing plants. I promise or your money will be refunded ;-)

Thanks for the advice. I do use a container mix recommended for vegetables but I am guilty of not watering as well as I should and also of not regularily using fertilizer - I just assumed that since the container mix had fertilizer that that was good enough - thinking it through I realize that what fertilizer is there in the beginning needs to be replenished. I guess that part of my problem is that I keep trying to create a mini-garden in a pot - I've seen pictures where a tomato is combined with some herbs in one container - like a salsa garden - possibly my not fertilizing has something to do with the poor production and unsightly appearance of these past efforts. I will try again this year

Fern

Great advice from justaguy!

Fern, you could use that long, shallow planter for a single row of 'greens' of some kind....leaf lettuce, mustard greens, etc. It would be kind of small for much else.

Do you recommend any particular varieties of Cucumber and tomatos for container gardening?

Hi! I've had some success with patio tomaotes and spacemaster (I think that's right) bush-type cucumbers in 5 gal containers. (Lets be honest, I just used buckets.) Gypsy peppers did well too - about any pepper really. I actually grew a Big Boy tomato in a 5 gal bucket once. It gave smallish 4 - 5 inch tomatoes instead of the huge ones and by the end of the season it was so stunted and root-bound it gave only cherry-size tomatoes, but it did give ripe, good-tasting, tiny tomatoes.

I've never gotten massive yeilds in buckets/containers, but I always get something. I suspect it's because I've never paid that much attention to caring for them and seeing they have the food and water they need. I'm hoping for better now that I know more about container gardening.