earthboxes, maters and lime

[username5]

Hi there,

I have read the instructions for earth boxes that say everything one wishes to grow in them can be grown with whatever potting mix, a band of fertilizer and keep the water reservoir full.

The only exception I have seen is tomatos. The instructions for maters says they require a higher ph than most other things so add some lime.

I don't get this. Prior to reading the earthbox instructions I have never read anywhere that maters want a higher ph than the average plant.

Anyone know why lime is recommended? Better yet anyone grow maters in earthboxes with and without lime?

I am guessing the instructions are simply trying to prevent blossom end rot by ensuring sufficient calcium is in the mix and the ph isn't really relevant, but thought I would toss this Q out to the group.

[cukes]

I have been growing maters in self made E-boxes for 3 years now.
I add hydrated lime to the soil mix primarily to stop BER.
Not to sure about the other issue with PH.
I read somewhere that your water Ph has more affect on the containers than whats in the potting mix.
Had an excellent mater crop this year in the containers.
Bill

[username5]

Thanks Bill!

I guess what I am primarily interested in is whether there are earthbox (or similar) growers who do not use lime who don't have BER issues?

I have grown plenty of tomatos in the ground, raised beds and various containers and not once have I used lime or anything else intended to supply calcium. I *do* use home made compost that saw plenty of eggshells added along the way, but that's it.

The primary place I have seen BER is in the ground, not my raised beds or containers, but I pay more attention to moisture levels in the raised beds and containers.

This leads me to believe even moisture levels are more important.

If I am correct, and that's a big if, it would seem an always moist earth box should grow BER free maters without the lime added.

[amideutch]

Send an e-mail to steve.lott@earthbox.com. He's the go to guy for earthbox questions. Ami

[feldon30]

Potting mix contains lots of peat. Peat moss is acidic. Beyond that, I know nothing.

[username5]

Originally Posted by feldon27

Potting mix contains lots of peat. Peat moss is acidic. Beyond that, I know nothing.

Yeah, the peat is acidic, but commercial mixes have lime added to them to bring the pH up to near neutral.

I think I will email earth box as amideutch suggested and see what their reasoning is. I know what their reasoning is from their web page, it just doesn't make sense to me tomatos would require a higher pH in an earthbox than everything else.

[username5]

Well, I emailed as suggested last night and had a response this morning. Impressive turn around time.

This is the response for those interested:

It’s a little of both. The overall range pH range for tomatoes is generally considered to be about 6.0-7.5. Mid to upper 6’s work great for every variety I’ve ever tried. Most potting mixes, when first purchased, are pH adjusted (with dolomitic limestone) to be around 6.5. Peat based potting mixes become more acidic as time goes on (as in subsequent planting seasons), so for future seasons using the same mix, adding some liming material is essential.

As for the calcium, that is the other half of it. When used properly, tomatoes in EarthBoxes get very large and heavy with fruit. These large plants have a high demand for calcium, which we supply with dolomitic limestone. We still have problems with blossom end rot if we don’t use a liming material, even with a fertilizer containing a high calcium content. As a caution, if you don’t use it, you may have to do a mid season fix to correct blossom end rot, be it the addition of hydrated lime to the water reservoir or a foliar calcium spray.

Let me know if you have any questions, and good luck in the spring. I hope you like your EarthBoxes as much as I like mine.

[username5]

Been doing some thinking on this and I have come up with a hypothesis.

I think the BER problem in earthboxes may be the result of too much fertilizer.

Typically if their is sufficient calcium in the soil and the moisture levels remain relatively stable BER shouldn't be much of an issue.

I have never used lime on anything and don't see any reason to start now since potting mixes are already pH adjusted with lime.

An earthbox should do a good job of keeping even moisture levels as well.

So, if the fertilizer supplies the calcium and the covered, self watering container maintains an even moisture level, what would cause the BER?

My hypothesis is that the instructions for the earthbox call for way too much fertilizer. The instructions call for 2 cups of synthetic fert or 3 cups of organic fert. An earthbox should have 2 tomato plants in it according to instructions. Since it is a closed system there is no fertilizer run off.

I suspect the high amount of fertilizer may result in a nutrient lock up where the calcium becomes difficult for the plants to uptake. The lime would add much more calcium to compensate for the nutrient lock up problem.

What do y'all think?

I am thinking I will use an organic fert with a good amount of calcium in it, but only use 1 cup at most instead of the 3 cups the instructions call for. I will skip the lime.

[Worth1]

If you bought more than one earth box I would suggest that you did as the man said and put the lime in.
I won’t go into why I use lime and wood ash or wood char.
But I know quit a few folks that do and they have great results.
You just wont know until you try after all he has already done it.
I’m getting into the way the folks in the Amazon gardened and they had good results for years.
Look at this and look some more I think it is the way to go.
http://en.wikipedia.org/wiki/Terra_preta


Just my opinion.

[amideutch]

Username5,
I think what you need to address is what type of growing medium are you going to use, what is its PH and what nutrients does it have available for the plant.
From what I have read about BER it is caused by either Stress or Infection.
Stress can be caused by;
Low Calcium
Low Potassium
Low Boron
Low Nitrogen
Low Water
High soluble salts in the water. (Too much fertilizer?)
Infection is caused by climatic conditions that result in damp conditions resulting in fungus infestation.
So what may be causing one persons BER may not be the cause for anothers.
Ami