bdobs,

I would definitely add in at least a cup of Dolomite Lime ASAP, before your plants begin extending their root system into the potting mix. You can carefully trowel it in outside the immediate plant area down about 3", and it will disperse over time throughout the container.

This is what I bought at SummerWinds:

{{gwi:10474}}

Raybo

Thanks Raybo
I have the same stuff fom Navalets.
I put in in my other box, I just brain farted on this one

You are probably still going to get BER in the beginning of the season. It's just the way it is.

The lime will mostly just make the ph more tomato friendly, but doesn't cure BER.

I'm must be missing something here. Why would you want to add lime? Wouldn't that raise your ph in your boxes. Tomatoes do best in a media with a ph of 6-7. The potting mix I put in my earhtboxes has a ph of 7.5 at best. Is the calcium that important?

Calcium, in the form of dolomitic lime is indeed important since it will help get the Ph to the desired range. BER is caused by many stresses to the tomato plant. Overwatering can cause it, disturbing the roots also. Tomatoes do use calcium but adding it doesn't seem to stop BER. Apparently the calcium has to move through the plant easily and stressing the plant interupts that function. So, don't swear too loudly when the first fruits come down with it, might be stressful.

sprtsguy,

I had the same "mental problem" of adding Lime. When I measured the pH of the stock potting mix, I got a reading of 6.5, which is supposed to be the "sweet spot" for tomato growth. After adding in Lime, the pH read 6.9. So as jbann says, there must be something else going on here vs. just the pH reading as to the rationale of adding in Lime. The EarthBox folks are adamant in their video that adding in Lime is essential. May be one of those Mysteries of Life....

Raybo

The more peat you use, the more lime you will need. Period, paragraph.

Newbie here seeking your wisdom. Does the addition of dolomite only apply to those using the Earth Tainer? Mine are in potting mix in big containers and raised beds. Also I've been advised to put 2 regular aspirin into the planting hole. Does the aspirin serve the same purpose as the dolomite?

Thanks,

Andrea

Andrea,

The "EarthTainer" is simply a generic name I came up with to avoid any conflict with the good folks at the EarthBox Company, who are trying to protect their registered trademark. My design is a modification from "joshos" home made design, and there is nothing different from it pertaining to what to put in the potting mix.

Generally, for any container growing (especially tomatoes) it is recommended that you add Lime. I have read of others who add Epsom Salts instead, or in combination. Never heard of the aspirin additive, but others may help you out here from their own experiences.

I am doing an "A/B" comparison this year in a few of my EarthTainers with Lime on one side, and Epsom Salts added to the other side. Two identical plants, so I will post my personal experience later this year on which worked best.

{{gwi:1320207}}

Raybo

Generally, for any container growing (especially tomatoes) it is recommended that you add Lime.

I'm sorry mewste but I have to disagree with this. While I know that Earthbox now recommends adding it (they didn't use to) and while the results of your comparison study will be interesting, I don't think we can claim that "adding lime is generally recommended".

Adding lime to container mix is strictly optional. As far as BER is concerned, it is another of those old wives-tale fixes like eggshells, Tums, etc.

Many folks, myself included, successfully grow many things, including tomatoes, in containers without ever adding any lime to the mix. ;)

Dave

Hi Dave,

I DO hope you are right - as I spent $21 buying boxes of Dolomite Lime this year, and I would love to eliminate that expense again next year. Why then are the EarthBox people so insistent on supplying a first year starter kit of Lime in with every EarthBox? If they found it wasn't necessary, they could eliminate a cost of goods sold expense.

Do you make your own mix that may be different from commercial mixes like Miracle Grow or StaGreen? Perhaps for the average gardener who does not have access to blending their own mix as you may have, the instruction to add in Lime may be an insurance policy of sorts. Anyway, I'll be able to tell if adding in Lime or Epsom Salts results in better productivity in my EarthTainers later this year. ...the mystery continues.....

Raybo

Earthbox FAQ: "What is Dolomite? Is it used only for tomato plants?

Dolomite, or hydrated lime, can be used for any plant, although it is critical for healthy tomatoes. Tomato plants need a lot of calcium in order to produce healthy fruit; dolomite satisfies this requirement."

Nice, general, non-specific, cover-your-backside statement with no explanation offered. But "lime being critical for healthy tomatoes" is not conventional wisdom - depending on soil pH it can even be hazardous. And their statement reflects the old school of thought that lack of calcium in the soil causes BER. I would also guess that it is a way to raise their prices (which they have). ;)

No, I don't mix my own container mix. I use Pro-Mix BX or Metro Mix 360 to which I add low-dose, timed-release fertilizer and then feed periodically through the season. EB doesn't want you adding additional fertilizers of any kind at any time (per their FAQ) and that too is not conventional wisdom. But I can't see how just lime would compensate for a regular feeding of a balanced supplement.

Hey! if it works for EB which is an artificial enviroment anyway for growing, fine, but let's not assume it is the generally accepted way to go for all situations be they in-ground or containers. ;)

Dave

Here is a link that might be useful: Earthbox FAQ

Raybo,
Keep us informed on your experiment. I will be watching closley.

I use and organic granular fertilizer (Dr. Earth) and noticed it has some soft rock phospate in it which is one of the best natural sorces of calcium and phosphorus. So I'm not rerally worried about calcium. I wonder if all fertilizers contain some amount of calcium? Does anybody know?

sprtsguy,

I am evaluating productivity of 2 organic granular fertilizers (Fox Farms Peace of Mind, and TomatoTone:

{{gwi:1309395}}

Toy your question re: Calcium content, the Fox Farms contains about 5% Calcium:

{{gwi:1320210}}

While the TomatoTone contains 3%:

{{gwi:1320213}}

Raybo

The pH of your potting mix in your earth-tainer is determined more from the pH of your source water. If your source water pH is high, your media pH will slowly climb. Likewise if your water pH is low, the media pH will drop accordingly. The media will generally contain dolomitic limestone to adjust your beginning pH to about 6.5

If you are growing in an inert soilless peat based media like MG potting soil or Pro-Mix etc., you are absolutely growing hydroponic by definition.

With all the required nutrients, balanced pH and proper watering schedule you will have ZERO BER!

Raybo,

This is from last year so do you have the A/B testing results now? I'd love if there is any conclusion to be considered.

Last year i did not use dolomite and I had a lot of BER.

Also, last year I used a soil with slow release fertilizer and opted to not add 2-3 cups of fertilizer at the top. All my plants were weak and low producers!

This year I have followed the instructions and so far all plants are bigger then the ones planted in my raised beds.

Of course the reason for adding lime is to bring up the ph which when adding peat which is what your box will consist of is necessary. If you are planting tomatoes not so much as they like it a bit on the acidic side. For dolomite purposes please take the time to get the powdered form as it will work faster than the pelletized form.

I'm using grow bags for the first time this year, and added some lime to the soil mix. But apparently it wasn't enough because the early fruit is getting a lot of BER. So over the last 3 weeks I've been mixing 1 cup of Pelletized Dolomitic Lime in 1 gallon of water (it dissolves fast) and I splash about 2 cups into each grow bag. Probably done about 5 applications now and the BER is finally going away. I probably could have added more, more quickly, but I was afraid of doing too much at once. I may have been underwatering too as the heat kicked in during June (I'm bottom watering the 7 gal fabric bags, which are sitting in 2" deep saucers), so I'm filling them 3 times/day now via drip line.

Initially the only lime I found was at HD (Epsoma 6.75 lb bag for $5), but then I found a Tractor Supply Co store nearby that has 40 lb bags of Pelletized Dolomitic Lime for just $4. Way better deal. So I have plenty now.

I checked the pH and it's still around 6.5 in each bag, so the lime doesn't seem to be raising it too much. My soil mix is a 3-3-1 ratio of peat-compost-perlite. This is the first year I'm trying everything like this (and growing from seed), so I'm still learning. But so far the results look pretty good (zone 5b).

" I may have been underwatering too as the heat kicked in during June"

As is often discussed here in great detail, that water issue, not the lack of lime was the cause of your BER.

"I'm bottom watering the 7 gal fabric bags, which are sitting in 2" deep saucers), so I'm filling them 3 times/day now via drip line."

The poor wicking nature of the fabric pots - yes I use them too - has also been discussed here in the past even when using proper soil-less container mixes in them as recommended. They work much better with top watering. Your mix as described with compost would only increase the wicking and perched water table problems (not to mention the nutrient issues).

Strongly suggest you move your drip lines to the top of the containers and run the lines until the water begins to collect in the saucer underneath and plan to feed your plants on a regular basis as compost, especially in a container with no active soil food web, provides little to no nutrients.

Dave

If you're using fertilizer that is intended specifically for tomatoes, that will have enough calcium in it. I have never added lime to my containers. Calcium uptake can suffer in soil that is too acidic or too alkaline, so if working with a commercial pH-balanced mix, I would personally not add amendments that can significantly alter pH, such as lime.

I've only had BER issues with one of my container varieties, which is a variety known for early BER problems even when grown in-ground. I've grown other relatively large-fruited varieties, like some of the Dwarf Project types, New Big Dwarf, etc. and never had BER issues in containers despite never adding lime.

The biggest issues causing BER are

1) early fruits often have BER anyway, no matter what you do, and plants often just grow out of it

2) improper watering (both too soggy and too dry can cause BER)

3) lack of proper fertilization (too many people underfertilize, others use too much N, which can lead to big, quick-growing plants which then have problems catching up with transporting calcium to all parts of the plant)

4) varieties doomed to suffer BER, like Roma and many other elongated pastes

Container-growing just exacerbates the above, as the container is a smaller growing environment which has little real wiggle room/buffer when it comes to temp, water, and nutrients, so stresses are magnified. The only other real difference is that, unlike growing in-ground where calcium deficiency in soil is very rare, a fertilizer including an easily utilized form calcium is key.

A well-draining mix which I water frequently and fertilize frequently at low dilution works best for me (not talking about sub-irrigation containers, which are a separate deal and one with which I have little personal experience).

Thanks Dave. I did also added slow-release fertilizer, lime, and epsom salts to the initial soil mix, but not a lot.

How often would you suggest feeding? I've been using Miracle Grow 24-8-16 dissolved in a water can every 2 weeks, but now that I think about it I'm probably not soaking the soil all the way through when fertilizing.

Thanks Gorbelly. Good info. The pH seems OK at 6.0-6.5 when I checked about half the bags yesterday (for as accurate as my cheap probe is, anyway).

Good to hear that early fruit often has BER anyway, as that seems to be the pattern I'm seeing. Most of the newer ones look better now. Still getting some BER on early ripeners but not as much as I had 3 weeks ago. Most of the fruit is small too, but now I'm finally seeing some getting bigger. I have a Homestead plant that I've pulled a dozen ripe tomatoes from, but they were barely larger than cherry-size. Now it's got green ones that have grown to billiard ball size, so it's slowly progressing.

Probably gonna take me a few years to figure out the right balance on all this. I'll redo the drip lines next season to top water and see if that helps (and supplement hand-watering the rest of this season). It's my 3rd year growing tomatoes but 1st in the bags. My in-ground garden space is limited so I'm using it for other veggies now, while the tomatoes and peppers (and a few cucumbers) are all in bags this year.