If I were giving advice to regular gardeners, I would say this:

Keep records of what varieties you plant where, every year.

If I were giving advice to super tomato enthusiasts who already follow that advice, I would say this:

Breed some plants!

Fertilize more.

When all else fails, grow SunGold.

In my climate, people grow tomatoes protected, in a green house or under plastic. If I think about the biggest mistakes I made so far, I would list too many plants (as they grow larger than you would think), too little water (as they are more thirsty than you would think) and too little ventilation (as they should be fried only after the harvest, not before).

I would advice to invest in automation, both for watering and heat control. I hope it counts as one advice.

Growing too many tomatoes is a disease and cannot be cured. Then you just need more space to grow more. (That was not an advice, just stating a fact.)

Pippin wrote: ↑Sat May 08, 2021 11:51 pm
Growing too many tomatoes is a disease and cannot be cured.

Bower wrote: ↑Wed May 05, 2021 3:37 pm My one advice would be to trial lots of varieties and find the ones that are keepers for your climate.

YES! Exactly! It takes most of the other problems and throws them out the window.

Totally agree with Bower as well about finding varieties that works with your climate, and this forum has been so great with that because we got such a broad geographical range of growers!

My other advice is to give a variety a second chance at a different area of the garden, it might just do a complete 180. Also pay attention to your growing season beyond just the zones because same zones in different parts of the globe can have very different climates in terms of rain, humidity, etc.

fluffy_gumbo wrote: ↑Tue May 11, 2021 9:05 am My other advice is to give a variety a second chance at a different area of the garden, it might just do a complete 180. Also pay attention to your growing season beyond just the zones because same zones in different parts of the globe can have very different climates in terms of rain, humidity, etc.

This will be especially apropos next year--in one of my raised beds all of the plants, including a proven winner, just are NOT doing well. Thankfully some of them had multiples elsewhere, and the one that's particularly bad I've grown before and have a better idea of it's potential. I've also had years where the top tomato from the year before was underwhelming, and some where the mediocre became the next year's star. Unless I just don't like how they taste or have something similar that does demonstrably better (Cherokee Carbon or JD's Special C-Tex vs CP, for example), it takes me at least three seasons to decide whether to keep or cut.

See, I knew I was right. Join a growers forum and you get all this marvellous advice for the price of 1 piece of wisdom.

Get a soil test, esp. when starting out. Often people think that because things didn't grow well, they must need more food, so dump more fertilizer next season! But there could be an excessive amount of some nutrients, but not enough of some others, and there's only one way to find this out.

What a wonderful way to get unlimited number of great advice by asking for only one advice!

My advice is what works well for me for all of my plants, not just tomatoes, in the center of Pennsylvania: Start with deep, rich soil and feed it with compost every year or two.

More specifically: Start with a raised bed that is 12" tall or taller, fill it completely with a 50/50 mix of topsoil and compost (not mushroom compost) with a layer of biodegradable mulch of your choice. Every year or two, top it with a few more inches of compost and more mulch. No need to till or to add anything else but plants, seeds & water.

WoodSprite wrote: ↑Thu May 20, 2021 5:34 pm My advice is what works well for me for all of my plants, not just tomatoes, in the center of Pennsylvania: Start with deep, rich soil and feed it with compost every year or two.

More specifically: Start with a raised bed that is 12" tall or taller, fill it completely with a 50/50 mix of topsoil and compost (not mushroom compost) with a layer of biodegradable mulch of your choice. Every year or two, top it with a few more inches of compost and more mulch. No need to till or to add anything else but plants, seeds & water.

Why not mushroom compost?

My advice is simple... "grow your own"! Do what you need to learn... grow in ground, but if you can't then just grow in pots... they taste soooooo much better than store bought! Now don't think for 1 minute that i'm putting these roadside stands down one bit cause that is how I learned what the taste difference was and started learning how to grow my own.

All the above advice is extremely useful. My one piece of advice to people I give seedlings to at this time of year in this area is always to plant in the late afternoon and shade their plants at planting because our climate goes from winter to summer overnight and it is so easy to burn the plants when you first put them in. I have learned this the hard way and my plants have done so much better (especially eggplants) by following this rule for at least a week or more. If I run out of shade material I will grab anything including a tee shirt or apron to throw over the top of the cage to shade the plant.
We had 38 degrees in the morning a few days ago and now we are hitting 85 each day. Tomatoes are not hardened off yet because I didn't dare put them in my table tent until two days ago. Until temps drop a bit can't even consider planting them. They are too tender to burn up. But with this crazy heat shading will be mandatory!

[mention]Gardadore[/mention] You are right on with your advice. It seems that no matter how much you harden them off, once you take them out of the container to plant, the heat, wind and sun starts to try to weaken them. And especially on peppers. I pull a section of field fence, bent in the shape of a dome over the bed and place a piece of shade cloth on top and leave that in place for at least a day or two. And for cucumbers, squash and okra that I start in cups, I make sure that I plant those in the evening, so the sun doesn't wilt them.

"What is the most important single thing in tomato growing?"

Trench them in.
I often don't do this myself anymore, because I start the plants later and put them in most times when they have about 3 or 4 leaves. They go straight down in through the hole in the black mulch. But for a novice or even most average gardeners, they buy plants that are big and sometimes even ready to flower. Those plants should have all the leafs pinched off except the top few, and planted at a 45 into a trench, then backfilled to just allow those top 3 or 4 leaves above ground. That tip will turn right up toward the sun and the entire rest of the plant will become an excellent nutrient mop in the upper, warm, nutritious soil. It is a simple way to make the strongest plant possible.

My advice is this just breathe !!! there will be failures and successes ask questions and it’s ok to second guess things rethink and complain it’s just part of it !! Enjoy the moments when there are good and even when they are not .have a glass of wine that always helps

JRinPA adds advice I also give along with shading. I hate to trench because I have been known to bend the plant a little too much but no choice when they get super tall like this year. No matter what I also tell friends to remove bottom leaves and bury the seedlings up to their “chins”! You don’t have to trench to do this on shorter plants and it makes a big difference in the strength of the plant as it grows!

When growing indeterminate plants learn to prune to 1 or 2 main stems and keep leaves down to minimum. I cut off all leaves below the first truss and as they are picked the leaves to the next truss are removed. Works great here in the heat.