Considerations when growing tomatoes in containers

Joined Nov 6, 2004
Hi all,

I have a couple of container grown tomatoes this year and I'm getting so-so results.

I've got four containers total. Two of them have San Marzano plums growing in them and two have a variety which I cannot remember (it's a slicer).

I started the pot out by putting some coconut liner in the bottom followed by potting soil. The San Marzano plants were grown from seed and the plants have been doing well. The slicers were bought online and are also doing decent.

I get good flower production and good fruit production. On one of the slicers I have been getting good fruit throughout the ripening process. But on the other plant I'm getting what started as some bad blossom end rot. I'm also getting bad blossom end rot on both the San Marzano varieties.

I use a tomato fertilizer once a week and have been spraying the entire plant with "Rot Stop" (calcium chloride) once a week. This did help the "slicer" plant some but not entirely. I then started to add dehydrated milk to the soil once a week and watering in. The helped a little more with the blossom end rot on the slicer plants, but again...not entirely on the one plant.

The San Marzano have blossom end rot so bad that nearly all the tomatoes are garbage :mad:. I've also got a problem with the San Marzano where the fruit is just starting to turn red and they fall very early with , as I said, bad blossom end rot.

I originally had some herbs, such as Thai and Italian basils. But I took the plants out and replanted in case they were taking up too many nutrients. This may have helped, but I had no visible difference.

I am wondering if there is anything to improve my success this year...and for next year.

thanks for listening,
Joined Aug 11, 2008
The only thing may be a bit too much fertilizer...

Blossom end rot, you know, is usually the consequence of Calcium deficiency and water Management.
You are using a Calcium additive so that is Good.

Are both containers set up to drain the same?
Have they the same soil mix?

But just like all living thing, each plant does have the possibility
of Genetic mutation and one of you plants is just not "right"

You will enjoy our video series on

Growing Tomatoes, go to and look for Playlist
Growing Tomatoes for Health and Wealth
Joined Nov 6, 2004
Chuck, Thanks for the comments and the youtube link.

I haven't been using as much fertilizer since I took the herbs out of the pots. I had Basil growing all around the plant in each container, which I think may have been a bit much.

Both containers are set up the same with a layer of coconut liner in the bottom with a Miracle-Gro soil mix.

So far we've only had a couple of ripe tomatoes. But finally we're starting to get a good batch that look like they may ripen better. Maybe the damage was done to the first batch of tomatoes before I started adding the calcium. Of this current crop they all look better, with exception of a few San Marzano.

Maybe it just took a while for the calcium to get stabilized into the plant, and fruit?

thanks a bunch!
Joined Nov 6, 2004
Well...even though the tomatoes started off having some problems with blossom end rot they ended up quite nice. As I said...I used the spray and the dehydrated milk. Probably more of the dehydrated milk than the spray though.

I think it may have taken a while for the calcium to get through the entire plant and the fruit formation and stop the rot entirely. But now...finally...I don't have a single tomato with "the rot" :bounce:

I think I may just add some evaporated milk into the soil before I put next years tomato plants in the pots.

Joined Nov 6, 2004
I wish I could remember what "slicer" I ordered. They had a nice well rounded flavor. Border line almost too sweet...but still quite nice.

The San Marzano plums had a nice complex taste to them. But The skin on the ones I grew were pretty thick. I'm sure fine if you were peeling them and making sauce...but a bit too thick for regular day eating.

I'd love to hear any suggestions you may have on a variety that you feel grows well in zone 5...and is bred for taste. I'd like to stick with one "slicing" type of tomato and one Roma type.

Joined Feb 1, 2007
The causes of BER are not well understood. That's how scientists (in this case, botonists) say "I dunno."

What we do know is that it's associated with a calcium deficiency. However, that doesn't necessarily mean an absence of calcium in the soil. It usually means that the calcium is not in a soluble form that the plant can use.

That is one reason that BER usually effects only the earliest plants. The cold, damp soil doesn't allow the plant to take use the calcium that's present. Later, as the soil warms, the calcium more easily goes into a soluble form, and the plants utilize it.

Granted, container gardening presents special challenges in terms of nutrition and moisture management. Even so, the same methods that work in the ground should help in a container.

To help free existing calcium, add a tablespoon of epsom salts to the hole before adding the plant. In fact, my procedure is to put a handful of compost in the hole. Add the epsom salts and the contents of a book of paper matches. Another handful of compost. Then the seedling. Backfill the hole and draw a circle around the plant with powdered milk.

I haven't had one instance of BER since starting that system. It's certainly worth a try.
Joined Aug 13, 2008
Dan - I believe our growing zones are similar. I'm in upstate NY near Albany which is zone 4 or 5 depending on who you talk to. For the last 2 years I have planted one tomato plant each year with great results. The type is called Better Boy and it is a slicing tomato with very good taste. I do plant mine directly in the ground (not sure if that option is available to you) in an area that gets around 4hrs. of morning sun and about 2hrs. in the afternoon. The soil is very sandy and drains very well. Believe or not I get my plant at the local Walmart and plant it usually in late May when the threat of frost is usually passed. I don't do much else to it - maybe a little plant fertilizer -that's it. I believe that less is more with plants. The tomatoes are around the size of a baseball and a nice ratio of juice to meat. Last year we ended up with 38 ripe tomatoes and another dozen green. This year we're at 32 picked so far but I think we're running out of time at this point.

I guess my point is if you can get them in the ground with good drainage and abudant sun you should have better luck.

Hope this helps,
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