How many tomato plants in a 20 gallon container?

[Gardenboy]

I have always just grown 1 indeterminate tomato plant in a 20 gallon container. Would 2 plants be okay?? Any information would be helpful. I guess I could experiment and find out...

[KarenO]

I routinely plant 2 large and sometimes 3 in a big pot and I like the full way they look. I put them on the deck and they have a decorative purpose to some extent. here's a pic to give you the idea.
I know others would say no but I do it all the time (mind you in a much different climate). They are very thirsty and need a lot of fertilizer keeping in mind two plants need more of everything than one would.

in the first picture, on the left is 2 Pink Berkeley tie dye plants in one pot and on the right 2 Captain lucky plants. The other photo is of my "tomato tree" as I call it. This one has 3 large indeterminate cherries, blush, super snow white and Dr. Carolyn pink all in that pot. Looks like one giant plant with 3 colors of tomatoes on it and it grew to be about 8 feet tall this year.

Long story short, if you are prepared for the extra watering and maintenance it can be done successfully.
Karen O

[Ed of Somis]

I would have to defer to K and others who have actually done it. I think her climate may help...and thinking this could not be done in Texas. I have certainly seen and heard of gigantic/productive single plants in 20 gal pots/cans. This is actually my exact plan (20 gal Husky trash cans) for next year. My biggest question: exactly what potting mix (custom or commercial) should I use.

[JamesL]

GB,
I now routinely put 2 per 20 gallon with no issues. Sub-irrigated Earthainers.
Can't imagine you would have any issues with "regular style" containers other than increased demands for Fert and water as Karen pointed out.

Nice pix Karen.

[KarenO]

Thanks James and Ed, I use commercial promix or miracle grow potting mix enriched with compost about 3/4 mix 1/4 compost to start off. I have no issues with bugs or diseases that overwinter here (advantage of a cold climate)so I re-use my mix from year to year and I just fluff it up in the spring and add compost to refill the pots to a couple inches from the top to leave room for watering. I use ordinary pots with drainage holes, nothing fancy.
KO

[JamesL]

Karen,
Do you add lime? And what is your Fert scheme with that mix?
Right from the get go or is the compost doing the trick until later in the season?
I don't grow like that now but I might!

[KarenO]

no, I don't add lime. I add 2 tbsp. Epsom salts (magnesium sulphate) per plant at planting time and then again midway through the season and I also use a big scoop maybe 1.5 cups of slow release organic granular fertilizer mixed into the top 2-3 inches of soil and again repeated midseason. it does take pretty much daily watering to keep these big plants going as well. but I enjoy messing around with my plants so I don't mind. Also, I am not opposed to a shot of the "blue stuff" once in a while if they look a little pale it's not usually needed though.
KO

[JamesL]

Good info. Thank you!

[AKmark]

I have a plant in a 20 gallon this year that looks like it will yield over 35lbs this season, I have not added up weight where two plants are in a container, but I doubt they yielded more, I have several singles that topped 20lbs. One plant does get huge if you give it space, but two will not reduce yield for that container, but I doubt using two adds any weight either. Maybe put two or three different varieties in one container throughout your space to increase varieties used.

[amideutch]

I am growing Margaret Curtain and Tarasenko 6 in 20 Gal smart pots this year. If you are pruning your plants to a single stem you can grow two plants per 20 Gal container. If you are not pruning your plants as I am doing then the answer is no. Supporting an indeterminate plant with large fruits can be a bear in a free standing container without proper support.

Ami