I put organic plant food in the planting hole when planted mid February. Since then I have fertilized them twice. Once after the first fruits were about nickle sized and again about three weeks later. They are lush and green and roughly 8' tall with lots and lots of tomatoes. I fertilized my garden today through the drip irrigation system. However I turned off the water to the tomatoes so they would not be fertilized.

Yesterday I cut off a large heaping wheelbarrow full of branches off my tomato plants and added it to the compost pile. When they are growing 1-2" every day and its become a real chore just to keep up with tying them. Why or why would I want to fertilize them?

Not sure whats causing your yellowing. It could be your soil is not evenly moist or over watering or under watering or heat stress. Not really enough information to make a call.

Oops! I forgot the "With What?" I used a couple hand fulls of Tomato Tone in the planting hole. Then I use Fertilome 20-20-20. I taped two 35mm film canisters together and drilled a bunch of 1/16 holes in them. Fill them both up and put the lids back on. I then take out the filter for the drip irrigation system and replace it with the film canisters. Turn on the system for 30mins and the job is done. Once a month for the garden and every 6-8 weeks for the tomatoes or less if they look healthy. I see no need to fertilize large healthy plants that are growing and fruiting

Thank you for responding, thisisme.
Sounds like you have very good growing conditions.

My soil is pretty much Texas Clay.
I worked quite a lot of "stuff"
into this little area several years ago.
Then it lay fallow (except for weeds)
for a number of years.
Last fall I started adding dead leaves, etc.
It was pretty loose when I dug it up this spring.

I completely forgot to add any fertilizer
to the planting holes.

As to the slightly yellowing leaves,
I guess I will just have to wait & see.
Maybe, hopefully, it won't get worse.

Rusty

Disclaimer: I'm a beginner with tomatoes. I mixed mushroom compost, blood and bone meal, and epsom salts in the planting holes and also used the compost and blood/bone meal as top dressing for the whole planting bed. Since then I've been foliar feeding with maxicrop (seaweed extract) and mixing maxicrop and miracle gro organic choice liquid fertilizer in a watering can and watering with that once a week.

So far, so good. My plants look really healthy and they're starting to flower. I just saw the first tomato today, on a cherry tomato plant.