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katib_gardener

What type of dirt for above ground planter?

katib_gardener
15 years ago

I am getting an above ground planter put in at my house for tomatoes, peppers and maybe some herbs. It will be approx 18-24 inches in height and I will need a lot of dirt to fill it up with.

Does anyone know what I need to get? I called one landscape / rock / dirt company and they suggested a mixture of sand and mulch. The sand seemed odd to me. The guy said it was good for this climate (Tucson AZ) because the roots could get deep and they would not cook in the heat of the surface. Another company recommended "sandy loam" which is 1/3 top soil, 1/3 mulch, and 1/3 manure, but I am afraid the manure will generate too much heat (???).

Comments (12)

  • azruss
    15 years ago

    Greetings from a Marana backyard tomato gardener. I grow tomatoes in containers and small raised beds (about 18" cube). I don't know what the area/volume of your planter is, but I am not sure I'd use any top soil to fill it up. Tomatoes need nutrient-rich soil, so the first fill is probably going to be expensive, but it can be maintained and enriched over time. I'd use compost, coco peat, planting mix (which does include sand, mulch and compost) on top of a good soil amendment to enrich the earth the planter is built upon. The sand and mulch mixture doesn't sound bad, as long as you enrich it over the winter months with compost. A layer of chicken manure about an inch deep would be a good winter cover. Just make sure any mulch is all-natural, preferably organic, and not plastic. And the soil should not be packed tightly.

    Don't worry too much about the heat of the soil. No matter what you use, it's going to get warm--so warm that our tomato "growing season" is going to halt by the end of June. When the day temps get to the mid-90's and the night temps to 75+ consistently, tomato pollen becomes sterile and the flowers will just wither and die. At this point, any fruit on the vine will continue to ripen, but there won't be any new fruit.

    Email me if you'd like to share ideas. Also, I'm growing my spring crop from seed and I will have a few extra plants to give away for the asking. I'm trying out some heirloom and hybrid varieties said to do well, even better, in hot, dry climates.

    You might know all of this already, but choose shorter season varieties of tomatoes and start early. (I'm planting out sometime in January with Wall O Water plant protectors.) Our "season" really is pretty much over by the Summer solstice. russ.gladden@msn.com.

  • digdirt2
    15 years ago

    Here are links to several previous discussions on how and with what to fill raised beds. There are many more but these will get you started. ;)

    Personally, given the 2 options you have been given so far by the locals, I'd most definitely go with the "sandy loam" which is 1/3 top soil, 1/3 mulch, and 1/3 manure" - no problems with the manure.

    You'll also find a number of FAQ's and recommendations on this issue over on the Soil & Compost forum here and also in the Square Foot Gardening forum since that is what you will be doing. ;)

    Hope this helps. Good luck.

    Dave

    Filling Raised Beds

    How do you fill raised beds?

    What do I use to fill my raised beds?

    Filling raised beds with...?

    Need advice on soil for raised beds

  • dvdgzmn
    15 years ago

    This is for a planter, not a raised bed, right? You should check out the Container Gardening forum. Search for "Tapla" and you'll get plenty of interesting threads explaining the theory behind what's come to be called Al's mix.

    3 parts pine bark fines
    1 part sphagnum peat (not reed or sedge peat)
    1-2 parts perlite
    garden lime
    controlled release fertilizer
    micro-nutrient powder (substitute: small amount of good, composted manure)

    I've used this for about 5 years and it works fine. It degrades slowly so I replace 50% of the volume each year.

  • digdirt2
    15 years ago

    Good point! ;)

    But given the dimensions listed and the comment "need a lot of dirt to fill it" and all the plants listed as planned, I 'think' (and assumed) we might be talking about a raised bed rather than a planter - at least in the usual sense of the term. But maybe not. *shrugs*

    On the other hand, if one can afford it, there sure isn't anything wrong with filling even a raised bed with Tapla (Al's mix) - works great!! - as does Mel's Mix. ;)

    Dave

  • katib_gardener
    Original Author
    15 years ago

    Sorry, not too sure on my terminology. What I am having built is a retaining wall against my existing retaining wall that will hold dirt, around 66 linear feet and it was estimated that I need around 15 cubic yards of fill material. I'm not familar with Tapla or Mel's mix. The contractor said I could have "fill dirt" delivered and they will haul it to the backyard and fill the planter. I said I would do the research on what I wanted delivered. He estimated $1000 for the "best" quality fill, and that was in the ballpark of what I expected to spend.

  • dvdgzmn
    15 years ago

    What you have there is a raised bed. I'm not sure what "best quality fill dirt" is, but it probably ain't topsoil. I've only been to Tucson once, but I expect it's mostly sand. You'll need to mix in lots of organic material, but not 1/3 mulch as it will lose too much volume as it decomposes. Use fully or partly composted manure or other organic material. Some raw manure will be fine, too. Don't worry about it generating too much heat. Once it's mixed with all that sand it will decompose very slowly. A landscaper is not necessarily a gardener. Your local Ag Extension would be a better source of advice.

  • digdirt2
    15 years ago

    And unless things are 5x more expensive in AZ vs. around here you should be able to fill it and fill it well for MUCH less than $1000! Bagged composted manure sells here for $1.50, same for bags of what they call top soil. Bales of peat for $9-11, good quality containers mixes go for $7-10 for the 5 cu. foot size, and sand for $3-5 per 50 lbs. bags, etc.

    Have a "fill my raised bed" party with a bunch of friends. ;)

    Dave

  • katib_gardener
    Original Author
    15 years ago

    Well it sounds like I need to do a lot more research. I will visit the nursery down the road and see what they recommend and as you suggest talk to my extension office. Just curious, I don't think I've ever found manure, peat, and container mixes for that cheap here. The only places I've found that sell this type of stuff around here are HD and Lowes or Walmart and they are all very simialr in price (or nurseries which are typically more expensive).

  • dvdgzmn
    15 years ago

    I guess it depends on how close the nearest industrial feed lot is. Here in N California there are massive feedlots a couple of hours away in the central valley so you can get composed manure for $1 a bag at Lowes.

  • digdirt2
    15 years ago

    katib_gardener - got a Walmart, Home Depot, or Lowes, Farm & Fleet, or similar. They sell all these things at very reasonable prices like I listed above during gardening season - early spring and summer here - not sure when that would be in AZ. Maybe there just isn't much demand for it there and thus the much higher prices.

    Maybe a borrowed pick-up and a trip out into the country where soil/compost supplies are more plentiful is in order. ;)

    Dave

  • andreajoy
    15 years ago

    you need a planter's mix. something that is part mineral content (top soil or sand) and part organic matter (manure or compost). personally, i would go with a top soil/compost mix.

    the sand and mulch mix sounds like garbage. for one, it won't have any nutrient content to it at all. mulch isn't compost. second, sand isn't desirable for gardening. it won't hold moisture and you'll forever be fighting it, trying to add organic matter, only to have it decompose too quickly (especially in your heat.)

    I filled my beds with top soil/compost mix. i also live in a very hot climate. the one problem i did incur was that the soil delivered to me was hydrophobic. i think this was due to the soil sitting in a huge pile somewhere, baking in the sun. at the time, i didn't know you could just spray your soil with a little soapy water and all would be right with the world...so i added more compost, a lot more. needless to say, i had very large, green plants that year.

    also, it sounds as if your raised bed is large enough that you won't have to worry about "cooked roots."

    if your only options are these few places you called, personally, i'd go for the sandy loam.

  • jack_sarnese_com
    13 years ago

    can I use mirical grow potting soil for herbs and tomatoes?

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