How do you calculate how much soil you need...?

Hello!

I'm moving from a garden-less apartment to a house with a yard in a week. I'm starting a self-watering container garden for vegetables, and herbs. Planning on doing at least 4 or 5 (my list keeps growing!) of 18 gallon containers for carrots, eggplants, and a number of other veggies, and some shallow ones for salad greens. Probably a few 5 gallon containers as well, after seeing all these great ideas.

I've got both the "Incredible Vegetables from Self Watering Containers" and "Stucky and McGee's Bountiful Containers" books, have read them cover to cover, but still have no idea how to figure this out.

How do I calculate ahead of time how much soil I need?? I have nothing (no really, I truly am starting from scratch), so everything from compost to peat, to blood meal I need to purchase. I would ultimately like to mix my own mix too.

But mainly, how do I determine overall how much soil I need? How have you solved this problem before? Attached is a (bad) picture of my new backyard from the real estate listing if interested.

Well, this is a tough question to answer(at least for me). I just keep buying 1.5 cu.ft. bags of potting mix until I don't need anymore :)

First thing....regular garden compost is a bad idea in SWCs(Self Water Containers). Too heavy and stays soggy. A slow death for your plants. I have never mixed my own SWC soil because I have found a good medium that works for me without having to add anything to it. Even at $9 per 1.5 cu. ft. it's worth it to me. Some people buy cheaper potting mix and add Bark fines, Peat and perlite to it. Seems to work well too. There's a lot of people here who use coir with great success. Hopefully they can tell you more about it.

I start out by buying a huge 2 cubic foot of perlite, then I use coconut coir and can usually get quite a few containers, depending on size, per blocks of coir and perlite mixed. If I'm using potting mix, I just buy the huge bags, and buy quite a few of them and just go get more as I need them.
joy

If you want to do it math-wise, 1 gallon = 0.1337 cubic feet is a useful conversion factor. Sounds like you're in a range where it's sort of a lot of bags, but not worth a dump truck.

I think some of it is cognitive style - some folks like to calculate ahead, make one grand trip to the store, and pot 'em up. Other folks get a modest supply to start, then shop as they go. Either is fine.

Probably you've already done this, but think too about where the containers need to be, how you're going to move them or move the dirt to them, do you need a cart or wheelbarrow, should you hire a guy or borrow a pickup, etc.

Have fun! Keep us posted...

One (LARGE) 2.65 cubit liter bag of Miracle Grow Potting MIX (remember, only MIX for containers...) will fill approximately three 5-gallon eBuckets. Depending on what you're growing.

Brassicas (cabbages, broccoli, cauliflowers, kohlrabis) like highly organic growing mediums, so I usually add my homemade compost and leaf decomp to the MG in a ratio of MG:compost:leaves of 2:1:1 -- or 1:1 of MG:compost if no leaf decomp is available.

So, then, my MG will stretch to fill six eBuckets!

After trying various methods of container gardening for about 10 years now, I think the the best advise I could offer you is to begin your gardening career with products and advise from this site: www.instagarden.com. His kits are great for starting out a garden with proven products and expanding it later. You will wont to experiment around with different growing mix and systems later on but these proven gardening kits are a great way to start.

As far as how many plants to plant in what size container.....I recommend the 5 gallon container method. Consider the 5 gallon container as being one square foot. Buy Mel Bartholomew's book, "Square foot gardening", and he has some great diagrams in there about how many plants can be planted in a square foot area. His book is not about container gardening but his charts and diagrams about how much to plant in a given area is better than most I have seen.

Thanks everyone!! Great advice from everyone, really, I do appreciate it.

Since it looks like I'm doing a mix of the 5 gallon ebuckets and my own 18 gallons, I really appreciate just the estimate of how much I need.

realbirdlady, you are right in saying that lots of bags but no dump truck. I don't have THAT much space!!

Ray and Joy, thanks for the idea about coir, I hadn't considered that before, and thanks too to Jaywhacker for the link! I'll definitely check his site out.

Gymgirl, thanks again for directing me to this forum, glad you could chime in too!

I will keep y'all updated!!

Kindle,
Here're the EB instructions website

http://mckarion.wordpress.com/2009/11/29/frugal-gardner-self-watering-bucket/

Of course, I find this only AFTER I have already gone and bought soil and compost, but it may be helpful for others out there:

http://ohioline.osu.edu/hyg-fact/1000/1647.html

This is a link to the Ohio extension fact sheet on container vegetable gardening. It has a nice chart about halfway down on estimating soil mix to use.

In the end, I decided to go with 4 5-gallon ebuckets, which were the easiest to make, and about 5 18-gallon or so containers for lettuces, carrots, and things that needed more depth or surface area. Will post pics in about a month!!

Nice, complete article. Thanks!

Update!

The garden is coming along well! I chose to do 5 EBuckets for zucchini, summer squash, green peppers, and cukes. I also did a few 18gallon containers for lettuce and carrots, where I wanted more surface area than depth. Everything except 5 shallow IKEA clothes boxes I converted to self-watering systems. The shallow opaque IKEA boxes are perfect for herbs with some drainage holes.

I have to say, after doing extensive research on this subject, the Ebuckets were the easiest and simplest to build, and required maybe 5 minutes total to build each one. Of course, it helps when you work in a carpentry shop and have access to a band saw, which made cutting the handles off the colanders a lot safer than a jig saw. And quicker.

I'm keeping a garden blog here on DG on my profile if you want to go see my urban backyard garden in progress. I'll also be building a composter and water barrels soon. Thank you all for the continuing education and support!! It's been just great!!

Another image of the whole garden. Sorry for the fading light!!

Kindle,
Lookin' good! Just a few observations/suggestions:

Once the greenery bushes up, you'll have to go hunting for the fill tubes. I suggest making them longer (next time) OR get some used plastic vacuum cleaner tubes and just shove em in as extenders. They work great! (Thank the DH for that idea...)

I usually put my fill tubes as close to the side of the eBucket as possible to not interfere with the root system. Just my quirk. If your's works, hey!

Covering the buckets with the lids keeps out the falling leaves. It also keeps the rainwater from splashing your fertilizer ring around and keeps the soil off of your bottom leaves -- less chance of mildew and fungus-y stuff growing up your stems, too...also, squirrels can't bury stuff in your eBuckets!

QUESTION: How did you outfit those white tubs I see? What's growing in them? Are they self watering, too?

REQUEST: Please LMK when you begin constructing your rainwater system. I may need to try to get one done where I'm going, to conserve water for the garden.

Thanks!

Linda

This message was edited May 25, 2010 10:18 AM

Linda,

In response to your questions:

The white tubs are for herbs. I decided not to do self-watering systems with them because they are shallow (about 7" tall) and many places recommended traditional containers for herbs. I drilled some drainage holes in the bottom, and will probably set them up off the ground a bit to facilitate better drainage. That is the most experimental part of my garden I feel, as I'm not sure how successful those will be.

Fingers crossed, I will be doing my rainwater barrels this weekend. I will of course post pics after. I plan on trying for a design from instructables.com, found here:
http://www.instructables.com/id/High-Volume-Rain-Barrel/

I've also attached a better angle shot of the herbs.

UPDATE:

Found a calculator that uses width and length, but ALSO how deep you want to fill that area (in inches!).

Gives you the answer in cubic yards.

http://www.areamulchandsoils.com/product_calculator.html

Hope this helps others as much as it would have helped me!

KindleKat,
Looks to me like you've got either a green thumb or a magic wand!

Linda,

I never expected lettuce to grow this well in this heat, it's only just now bolted (after four 100 degree days, can't blame it) or my swiss chard to get so huge. It's all thanks to the "self-watering" containers, and a great compost/soil less mix. Definitely am doubling the amount of ebuckets next year. The only thing that stopped my zucchinis and squash from taking over the yard from the buckets were SVB. Can't blame that on the buckets at all....

So yeah, I'm sold!

Squirrels also kept digging up my carrots and radishes, so I just built a cage right onto the container, and replanted. (see picture) This should keep them out!

Now I'm wondering if I can convert a salad table (http://growit.umd.edu/Salad%20Tables%20and%20Salad%20Boxes/index.cfm) into a self-watering system. I'm convinced that these greens would NOT be as successful or large had I planted them in the ground.

This message was edited Jul 13, 2010 4:02 PM

KindleKat,
Which design did you use for your self-watering HEBs?

Awesome Salad Table & Salad Box designs, too!

Thanks for the link!

This message was edited Jul 13, 2010 3:23 PM

This is what the clear ones look like. Used the lids as the barrier, and also the colanders just flipped the other way. These were certainly more time consuming, but maybe only by 20 more minutes or so.

The plastic barrier does sag a bit after the soil was put in, but so far does not seem to be a hinderance, and the wicking chamber has plenty of room for water.

Entire gallery of my garden is found here:
http://www.facebook.com/album.php?aid=2016921&id=152300249&l=974a449028

KindleKat,
I've looked at both designs. The first one with the overturned tub already has perforations around the sides. All you need to do in the future is drill some additional holes in the ends where there are none, then pack your soil tightly around all the sides, then more losely above the top of the tub, as usual. That soil packed around the tub will be in constant contact with your water and, in effect, becomes your wick. There'd be no need for a wicking basket in the middle.

BTW, where's your overflow hole?

I think I just cut your construction time by 25 minutes or so....

This message was edited Jul 16, 2010 3:24 PM

Gymgirl,
I wasn't sure if those holes would be enough for the wick, which is why I added the basket, so it's good to hear I shouldn't need it.

I put in a straw overflow hole after I took the photo, it was just on one side.

Thanks!

Kindlekat: I like the way your HEBs look, great brainstorming and I'll bet they work much better than my totes do, this is my second year on them.
joy

Kat,
How big are the blue tub and the white basket in photo #1? Are they Rubbermaid or Sterilite? That is a really KEWL and efficient design you've come up with.

If it's long and deep enough, it would be perfect for some container onions or garlic, or some beets, turnips or carrots (1/2 Nantes or short types), one veggie per eTub. The root crops could do well in one, too, if it's deep enough. And greens (collards or mustards, would do very well at the depth you show. A shallower design would make an awesome salad box for spinach or lettuce!

Great thinking "outside the box" to use that overturned basket as a wick. I'm seeing a "square" colander!

Linda

Linda,

Thanks! The blue tub is an 18 gallon container, Sterilite 24"L x 18.38"W x 15.75"H . The white basket is like this one http://tinyurl.com/24xlqhc but I'm not sure of the size. I bought most of my containers at the same time from Walmart, so I just fit-tested the baskets in the store till I found one that fit in the blue bin. I wanted at least 11" of soil depth for the blue bin, after I put the basket in. You're right, it is like a square colander, which is the idea! So far it grew one mostly-successful crop of radishes this summer season. I replanted after the squirrel got in and dug up all my carrot seedlings, so I'm on a second planting of both radishes and carrots. Early nantes and Purple Haze, actually. You were right on target!

Also, as I've posted earlier, the clear boxes had a similar soil depth (11-12" before hitting the water reservoir) and those are my salad boxes. I posted a pic a few entries back showing all my salad greens flourishing, and the last pic I posted to this topic is of the clear salad boxes empty, before I planted everything. Right again Linda! Swiss chard does amazing in these conditions.

I'm planning currently on a salad table design that is self watering like the ebuckets and my tubs. I'll be designing it this winter and building in time for spring planting. I have a feeling shallower versions of the square baskets are going to be key.

http://www.hgic.umd.edu/documents/HG601SaladTables_SaladBoxeslowres_001.pdf ^^_^^

Kindlekat, someone referred to this entry in my blog. I clicked it to see what it was referring to and what thrilled to see the splendid results your are getting and the great modifications you have been able to make so successfully.

I have been away from gardening since June, 2010 and not done a whole lot with my eBuckets. People like you and Linda make me so proud to be associated with the continuing success of this idea that started so simply just over a year ago.

Lane Cockrell
http://mckarion.wordpress.com/

Lane,

I'm sorry to hear you have been away for a bit. Your designs for the ebuckets made ALL the difference in the world in my first garden. No one could believe the success I've had with them. This springs garden I'm planning on tripling the number of buckets I had last year, plus using the concept to modify a salad table to be self-watering.

Thank you for keeping your instructions online, I've referred everyone who's asked about the buckets to your site. I can't wait to start growing things again because these have made it so easy and fun.

Hope you come back again soon!
Kristen