I've been following this thread and feel the need to make a few corrections, Folks.
Gymgirl and Joy are giving some good advice but with a few misunderstandings. Don't be alarmed, GG and Joy have sure learned a lot, and shared, in the little bit of time they've been gardening or on DG. Standing ovation to them both! Your willingness to help is wonderful, I hope you keep it up and encourage others to do the same.
"BER is where your tomato has a black spot on it close to the stem part,"
Nope, BER (Blossom End Rot) is when there is a black spot at the blossom end, the end opposite the stem. That is important to remember as it will tell you a great deal about the cause of that black spot, why it is at either of those ends, and what you can do to resolve the issue, if anything. (For example, a black spot at the stem end might be just plain rot, disease, elevated sun scald, etc, but certainly not BER.)
Also, Debi is in Australia, a totally different region than U.S and the growing conditions, climate, soil and soil products are going to be quite different so certain suggestions that we would follow in the U.S might offer and prove beneficial may not apply in Australia. For example, many commercial soil mixes are geared for regional use, what is sold in the South will oftentimes consist of ingredients that are quite different from what is sold out West. The same will be true for potting mixes sold here (US)) will be different from those sold in Australia, most likely due to what ingredients are available. Keeping that in mind it might not be such a good thing to recommend lime (of any kind) unless we know the pH of the Australian potting mixes. Moreover, recommending to "make sure you have added dolomite lime to the medium along with epsom salts" may be more harmful than helpful. It is also a bit redundant in that dolomite offers both calcium and magnesium so save your money, adding the Epsom salt isn't necessary for magnesium since that is provided in more than ample amount from the dolomitic lime. (And by the way, magnesium doesn't come into play with BER so it also is not recommended as a necessary ingredient to inhibit it.)
I feel uncomfortable making corrections here because I'm afraid it will come off as attacking. I assure you that is not the case. I hope ya'll understand I tend to talk and type in a gentle voice.
"Fertilize with a time-release fertilizer anywhere from 10-10-10 to 15-15-15" and "Tomatoes are nutrient hogs, so fert often."
Not. Time released fertilizer needs to only be applied once per season, not often. Those types of fertilizer, also known as CRF (controlled release fertilizer) usually come in 3-4 month, 7 month, and 9 month release rates. With tomatoes a single application of CRF will be sufficient. I wonder if Linda/Gymgirl mistyped that and was referring to regular granular fertilizer that many folks use directly in our veggies gardens, lawn, and EarthBox type containers. If you substitute granular fertilizer in her suggestion above I think you will do well. And by the way, tomatoes get by very easily on less fertilizer than many other plants, especially preferring a low Nitrogen food.
Back to Epsom Salts, it's simply not necessary to overload your soil mix on a regular basis with it. If you use CRFs they usually contain magnesium; some granular ferts also contain it; and it is also usually available if you are growing directly in the ground, sometimes to excess. However, Degarotty, that in-ground availability won't apply to you so I'd suggest seeing what your potting mix is made of and also check the ingredients on the fertilizer/plant food you purchased and see if it already contains mg. Too much will have a negative affect. And keeping in mind our environment, Epsom Salts is highly water-soluble and any excessive use will simply cause it to be washed out of our containers, into the ground and eventually be transferred into the local ecology. (A pet peeve of mine is the Epsom people stating it 'doesn't build up in your soil, you can't use too much', etc. The reason being is because it washes out and has to go someplace, eh?)
As for other suggestions, I whole-heartedly agree to move your plants into separate pots, no less than five gallon. Grosse Lisse can get huge and the better root system the better the harvest, the bigger the container the more it will hold water/moisture consistently and not have a wet/dry affect.
I sure hope I haven't stepped on anyone's toes here with these corrections.
Best,
Shoe
