My tomato plant is 8 ft tall, full of blooms and not producing. What can I do?
Too cold and wet or too hot and dry, are the two most likely reasons for your tons of blooms and lack of fruit.
This article may help you:
https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-blossoms-no-tomatoes.htm
The article I read says add nutritious matter to the soil. What would you suggest to add?
You can use organic compost to top dress your plants.
If you do not have your own compost, you can purchase bags at most garden centers and greenhouses.
Here are some links with more information.
https://www.gardeningknowhow.com/edible/vegetables/tomato/yellow-tomato-leaves.htm
https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-fertilizer.htm
https://www.gardeningknowhow.com/composting/basics/compost-as-garden-mulch.htm
I have dug up 3 plants because the leaves have wilted. Can I save the tomatoes by hanging the plant and root ball upside down in a relatively cool dark closet or cellar?
You can ripen your tomatoes off of the plants.
This article will help you.
What caused yellow spotted dead leaves on my tomato plants?
These articles will help you:
https://www.gardeningknowhow.com/edible/vegetables/tomato/early-blight-alternaria-tomato-leaf-spots-yellow-leaves.htm
https://www.gardeningknowhow.com/edible/vegetables/tomato/yellow-tomato-leaves.htm
Three tomato plants in individual pots. Planted several weeks ago and added marigolds to look nice. Plants were doing really good, growing healthy looking tomatoes, then leaves started turning brown and withering. Plants now look bad but the center stalk looks good. Tomatoes are plentiful but are a light green.
Check the moisture in the soil. Container plants need daily water and even twice a day when temperatures are above 80 degrees.
The soil should be light and well draining. Verify that the container has adequate drainage holes.
Here are some links to refresh you on the care requirements.
https://www.gardeningknowhow.com/special/containers/growing-vegetables-in-buckets.htm
https://www.gardeningknowhow.com/edible/vegetables/tomato/growing-tomatoes-pots-containers.htm
I have a tomato plant doing nicely but a stem has broken with two tomatoes the size of a pea. How do I save them?
Sometimes, if the stem is not completely broken, the tomatoes on it will still be able to obtain food and water and survive. If it is completely snapped in two, you could either throw out the broken piece, or attempt to re-root it in moist soil, perhaps with a bit of fertilizer and rooting hormone.
What causes such a fungus, I am assuming that is what it is, to grow on tomatoes? Too much water, too much fertilizer, diseased plants, etc? I have several tomato plants and a few of them are producing tomatoes that look great at fist glance, but when picked have a flat spot on the bottom that is mostly black with some white and brown spots.
Your tomatoes probably have what's called Blossom End Rot: a water-soaked spot on the bottom of the fruit where the blossom was. It's typically caused by poorly draining soil that doesn't contain enough calcium.
This article will tell you more about Blossom End Rot:
https://www.gardeningknowhow.com/edible/vegetables/tomato/tomato-blossom-rot.htm