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Joined: Fri Apr 26, 2013 3:46 pm
Location: Taylor, Mi

Miracle-Gro Garden Soil

Hello Everyone,
I'm new here and if this topic has already been covered I apologize.
Been growing several tomato plants in containers for many, many years. Some years are better than others as far as results go, as we all know.
Figured I would try Miracle-Gro Garden Soil this year because it was on sale & with rebate ended up being 99 cents a bag (fantastic deal). Got the bags home & noticed they said NOT for use in containers. Great! Rather than haul these things back, would it be ok if I just mixed SOME of this mixture into my containers with the existing soil? I don't understand how any kind of garden soil can be good in the ground yet bad in a container.
What would happen if I filled each container with ALL of this stuff? Would the plants go nuts or die?
Thanks in advance.

Greener Thumb
Posts: 955
Joined: Sun Apr 04, 2010 3:29 pm
Location: Central PA

Re: Miracle-Gro Garden Soil

zonk! "not for use . . " that sure caught my attention so's I went poking.

directions say mix 50:50 with natural soil. I suspect that is because it's got a fertilizer charge in it - which if it works perfectly with a 50:50 mix means there' twice as much fertilizer as needed (and strong enough to kill potted stuff) in the "un-mixed" version.

>>what would happen?

plants die.
tomatoes, as they don't need over abundance of nitrogen, could be all leaf&stalk, not too many fruit.

definitely sounds like something you'll want to mix with a native soil - personally I'd go 1:3 vs 1:1

Super Green Thumb
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Location: El Cerrito, CA

Re: Miracle-Gro Garden Soil

What else can happen is that the plants drown (root rot).

Products made for in-ground application, and many native soils, have small pore spaces (spaces between the actual soil particles, where air or water can be present). Containers with small pore spaces = roots that can't breathe, in a planting medium that can't drain. :(

Container mixes have larger pore spaces. This is why it's generally not a good idea to fill containers with native soil, but rather to create (or purchase) a planting medium with "air friendly" materials, including perlite, vermiculite, or other large, non-decomposing substances.

Does that help?

I have plants in traditional containers, and I have plants in large containers (i.e., raised beds). I also have roses in the ground, jade in the ground, a challenged fig tree (insufficient sun) in the ground, and lavender in the ground. Maybe a (very) few other things....

Cynthia H.
Sunset Zone 17, USDA Zone 9

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Posts: 2
Joined: Fri Apr 26, 2013 3:46 pm
Location: Taylor, Mi

Re: Miracle-Gro Garden Soil

Thanks for the responses!
I will try both of your suggestions. :)
I've never had good luck with regular-size tomatoes, tend to get lotsa flowers on extremely long vines and the yield is horrible. On the other hand, cherry tomatoes do the same thing but generally produce tons of the little guys.
My goal is for less vine on both types & end up with squat/bushy plants that produce a nice yield.
Maybe some day it will all come together.

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Super Green Thumb
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Joined: Sun Feb 15, 2009 6:04 pm
Location: TN/GA 7b

Re: Miracle-Gro Garden Soil

Tomato plants growing very tall and leafy with not much fruit sounds like too much nitrogen fertilizer. Tomato fertilizer NPK would be like 4 -7 - 10, lowest on the Nitrogen. But lots of flowers and no fruit sounds like something else. So it produces blossoms, but then the blossoms drop off without setting any fruit? I think there is a sticky in the Tomato Forum on blossom drop, which is a sign of stress in the plant.

Re the garden soil. Garden soil like top soil tends to be too heavy and dense for containers. Containers need soil that is light and fluffy. Otherwise it packs down and smothers the roots. Good additives for your garden soil to make it ok for containers would be peat moss, coconut coir, perlite, vermiculite, coarse sand, leaf mold or even just crunched up fall leaves.
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