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dominickg23

Why is dolomite important for self watering containers?

dominickg23
9 years ago

This year I gave my tomato plants 3 things;

Miracle Gro Moisture Control Potting Mix
Miracle Gro Water Soluble Tomato Food
Tap water, straight from the kitchen sink

I did not have any blossom end rot whatsoever.

I was looking into self watering containers for next year and all of the instructions say to add dolomite, especially for tomatoes-they act like it is absolutely necessary. Is there something inherently different about self watering container?

Just curious.

Comments (5)

  • scottsmith
    9 years ago

    I thought that dolomite was used to adjust the Ph.

    Here is a link that might be useful: Dolomite Use

  • suncitylinda
    9 years ago

    Self watering containers, like Earthbox rely on a potting mix that is primarily peat moss, which tends to get acidic. The dolomite lime balances that. When the PH is off, your plants are not well able to take in and/or utilize the nutrients. BER happens!

    I actually use Calcium Nitrate weekly in my EBs to guard against BER, but I always add dolomite each time I add new crops and fertilize.

  • seysonn
    9 years ago

    If the fertilizer used has already Calcium in it, you won't need dolomitic lime.

    And I don't see any difference between self watering and regular watering. In both cases tomato will need some calcium.

    With respect to BER, some varieties are just BER prone, no matter what.

  • suncitylinda
    9 years ago

    You can have all the calcium in the World, but if your growing medium is or gets acidic, as peat does, your plants will be unable to utilize it.

    I do agree with seyson that some tomatoes are prone to BER. Specifically those include paste types.

  • PupillaCharites
    9 years ago

    Hi Dominick,

    I have no need to supplement with calcium. suncitylinda is right, though, in that if you use a lot of peat you will have a soil on the too far acidic side. Use of agricultural calcium nitrate is not addressing the acidity, nor is it a replacement for a pH adjuster like lime, but rather it is used simply as a calcium fertilizer, which in another point she makes, will not necessarily treat BER.

    Since I garden in self-watering containers, I do not like to add pH adjusters just for the sake of adjusting pH, as it amounts to fixing something that isn't broken and that usually leads the wrong way ;-)

    The reason I do not supplement with calcium is because I get more alkalinity than I need from my tap water, and it tends to build up. No need to pay or do any work with a calcium supplement. That said, if you must add a calcium source pH adjuster, dolomitic lime is the way to go in a container, for chemical reasons, and better than most other non-miracle promising economical calcium products, when used in moderation.

    My bottom line is that if the tomatoes grow vigorously and the feed water is alkaline, the tomatoes do just fine with my acidic soil which tends basic as water is run through it.

    Controlling pH is like driving. Some people over correct all the time and make a job out of it, while others subject the plant to greater swings. I'm in the latter bunch, and my plants will tell me very obviously when they get sick and and adjustment is needed to get them moving again, which has never happened.

    I'm sure there is plenty of good advice to have in the Container Gardening Forum (see link). Keep in mind, many of the people giving advice think everyone has the same soil mix and irrigation water composition they do. This is far from the real situation so you mileage *will* vary.

    Happy growing
    PC, raining again, still ten days forecast of rain, rain rain. On the bright side, rain tends to drift the pH acidic, which both dilutes and slightly acidifies my pH since my containers get auto-filled in the rain ;-) Yay!

    Here is a link that might be useful: Container Gardening Experts