Got Raised Bed Gardening Questions?
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Well, the solution is simple. Leave a comment and let me know!
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{ 19 comments… read them below or add one }
How do I calculate the amount of soil I will need to fill my raised bed?
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March 11th, 2010 at 6:30 am
Great question!
I have two resources for you that help you calculate how much soil you will need for your raised bed, depending on size of the bed and the depth that you want.
http://www.plantanswers.com/garden_column/jan_03/4.htm
http://www.gardenplace.com/content/calculator/mulch_calc.html You can use this calculator to calculate each 4 inches worth of soil, and add it to together that way.
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I live in Florida and just finished building a raised bed for the kids. The plan is to grow easy vegetables (we have not figured out what yet) but I am now stumped as to what kind of dirt/fill to use. Again, we live in Florida so it will be pretty warm and sunny most of the year. The bed is about 3′ by 6′. Any suggestions?
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March 11th, 2010 at 8:23 pm
I highly recommend using the Square Foot Gardening soil recipe to fill your raised bed, even if you don’t use the rest of the method for planning and planting your garden. That soil recipe practically guarantees gardening success.
http://www.mysquarefootgarden.net/mels-mix/
I also recommend the Square Foot Gardening book, which you can buy at Amazon or at any bookstore in the gardening section.
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I am planning on growing climbing roses, however is a raised bed garden able to properly support them? And exactly how would you situate a trellis in relation to the raised bed?
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March 15th, 2010 at 9:27 am
Thanks for your question.
Yes, you can certainly grow climbing roses in a raised bed.
You could handle it many different ways. If you were going to put the trellis up against a wall or fence, you could create a three sided raised bed, against the wall. Or, you could build a four sided raised bed and put a trellis on the outside of one of the four sides. Just make sure that your trellis is sturdy and installed well, and you’ll be fine.
If anyone else out there has already done this, please feel free to chime in with more details about what you did.
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Is it possible to build a raised bed garden (flowers) on top of a concrete slab? I live in Northern Ontario. On side of the garden will be bordered with tall pine trees. What do you think?
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March 15th, 2010 at 9:23 am
Great question!
I have not tried this myself, so I did a little bit of searching for you and here’s what I found.
Yes, you can do it.
Here’s a great Gardenweb thread about it.
http://forums.gardenweb.com/forums/load/smallspaces/msg082156141678.html
And here’s an entire book about the subject, on Amazon.
http://www.amazon.com/Gardening-Pavement-Tables-Hard-Surfaces/dp/0881928127/
Please come back and tell us how you did!
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Is there any advantage/disadvantage from using either bricks
or concrete blocks to make a box for raised bed?
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lars Reply:
March 16th, 2010 at 3:57 pm
@Sharad.P.,
Thanks for your question.
From a gardening perspective, I don’t think there’s any difference. Both are safe to build a raised bed garden with.
I think mostly it’s a question of which one is easier for you to work with, and which one you prefer the look of.
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Last year slugs completely ruined my flowers, plants & vegetable gardens; I used beer traps, etc. I just could not keep up with them. Every day there was enough to make a stew for hundreds! Do raised beds help with this problem?
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lars Reply:
March 18th, 2010 at 11:32 am
@Karen,
No, a raised bed won’t make a difference per se. A slug can just as easily climb up the side.
Last year was a really wet year in many parts of the country, so perhaps the slug onslaught was related to that.
Here are some products you might consider:
http://www.cleanairgardening.com/organic-slug-bait.html
http://www.cleanairgardening.com/slugsaway.html
Eggshells around your plants are also a recommended option.
http://www.thegardenhelper.com/slugs.html
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Is it a good idea to cover (tarp) a raised bed after the growing season to preserve soil nutrition? This question refers to a raised bed that wouldn’t be covered with mulch or a cover crop.
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lars Reply:
March 21st, 2010 at 12:38 pm
@Keith Brace,
Good question!
I’d lean toward adding more organic materials or compost at the end of the season and tilling or spading it in, and then giving it all winter to make sure it’s completely broken down.
Or, you could do something like a lasagna gardening or trench composting kind of approach where you add a lot of materials that have not broken down yet, and let them finish over the winter.
I personally did not grow a cover crop, and also didn’t cover my own raised bed garden over the winter. I did add some more organic materials to my raised bed though, which gave it all winter to break down.
Here’s another good page that isn’t specifically about raised bed gardening, but covers getting ready for winter. He does mention using a tarp as an option.
http://www.helium.com/items/555030-how-to-prepare-your-garden-for-winter
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Hi-
What is your suggestion on the life of soil for raised beds?
I have 9 cedar raised beds for vegetables that took about 12 yards of mushroom mulch to top off .
This is my 3rd growing season in the beds. I rotate my vegetables and add compost. I have also added a few dozen night-crawlers to each bed.
The beds are full of worms (lots of small ones – so they arrived on their own, or are hatched from the ones I added).
The soil is still rich and dark…
What is the best way to keep the soil fertile?
I have heard that over time the soil will start to produce less vegetable. Will I be required to dig out 9 beds (12yards of soil) and add new soil?
db
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with a raised bed do different veg need differant depths like tomatoes, peppers, lettece, green beans
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lars Reply:
April 6th, 2010 at 12:45 pm
@Michael,
If you have at least 8 inches of soil, you should do fine with just about any vegetable.
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My problem is I already have an established garden, that has settled and “sank”.. I want to raise the whole bed, with a short decorative wall bordering it. I don’t think it needs to come up more than a foot or so. I guess my question is- can I dump dirt all around, and even over some of the existing flowers, and will they grow up through it okay? or should I uproot everything and start over? Thanks!
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lars Reply:
April 6th, 2010 at 12:47 pm
@Danette Lykins,
Your best bet would be to start over at the beginning of the season, before everything has started to grow.
If you put in a lot more soil now, it’s likely that you’ll end up harming your existing flowers because they’ll be buried too deep.
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I’ve just built two large raised beds used existing soil plus some added top soil ,multipurpose compost and manure.Is this the right mixture for these? I am a novice gardener and don’t know what to plant in these beds.Any ideas?
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lars Reply:
April 6th, 2010 at 2:54 pm
@marie,
Sure, that sounds like a reasonable soil recipe.
The manure is all well aged, I hope. If manure is too fresh, it can burn plants.
You can really grow anything in a raised bed from flowers to vegetables. So it depends on what you’re looking for in a garden.
If you’re going for vegetables, I always recommend growing what you usually buy at the grocery store. Because then you know you’ll really use it!
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Last weekend I planted my first garden ever and it is a raised bed planted with vegetables. I have been watering once each day and am now seeing LOTS of ants. Should I put something in it to get rid of these or will they even hurt my plants?
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lars Reply:
April 26th, 2010 at 12:57 pm
@Tricia,
I wouldn’t worry about the ants. I don’t think they will hurt your vegetable garden.
If it appears that they are crawling all over any of the plants and the plants are suffering as a result, a Spinosad based organic spray will take care of them safely.
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Hi, I am almost ready to build raised bed. What should I use to
prevent weeds from entering my raised bed from four sides and the bottom. I am not worried much about the bottom because
my soil is good and I cleaned it too. I went to Home Depot,Costco
etc and all of them says made out of recycled material and use for
flower garden,retaining wall etc but they don’t say vegetable garden. Are those ok to use in vege. garden? if not what should I
use? Any suggestion.
Thank you.
Sharad.P.
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lars Reply:
April 26th, 2010 at 12:56 pm
@Sharad.P.,
All of the landscaping weed block fabric is safe for vegetable gardening as far as I know. It’s just a thick fabric, and it isn’t treated with any chemicals that I am aware of. I used it at the bottom of my own raised bed vegetable garden!
If you’re worried, you can always use several layers of wet cardboard as your weed block. Or even more layers of wet newspaper.
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Sharad.P. Reply:
April 29th, 2010 at 12:27 pm
@lars, Thank you Lars,this will help me because there is a sell at costco
for big roll and now I can use that.
Sharad .
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Old carpeting works well, too.
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I am getting started on my first raised-bed garden. Someone told me that you can attach plywood to the bottom and then fill your box with your soil. Is this an option?
Andrea
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lars Reply:
May 6th, 2010 at 10:25 am
@Andrea,
No, not really.
Are you building a raised bed that’s on legs and lifted off the ground? Or are you putting it directly on the ground?
If you were trying to build a box on legs, then you could maybe put plywood at the bottom to hold the soil. But you’d want to drill a lot of holes in it, so that it could drain.
If it’s directly on the ground, you don’t want to put plywood on the bottom, because your raised bed won’t drain.
If you want to block any weeds from growing up from the bottom, just use several layers of wet cardboard, or thick layers of wet newspaper, or landscaping fabric. All of those will allow water to drain out, but will block weeds from growing up.
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Hello!
So, I know this is not the best scenario but I’m building a raised vegetable garden out of scraps my boyfriend had used for a fence. The problem is it’s weather-treated wood. He bought it recently so it shouldn’t be the CCA kind. Can I still garden happily? I know people recommend a plastic barrier but I haven’t found any specifics. Any recommendations?
Thanks!
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Well, it’s great you are recycling! If the lumber was bought recently, could you check with the store where it was bought and confirm exactly how the lumber was treated? Yes, a plastic barrier can be used between the soil and lumber. Here’s more information on construction materials for raised gardening beds.
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Hello,
I find your site very interesting !!!
I have a question about the lining in my raised bed on legs.
The bottom of the bed is made of hard wood planks 6″ wide by 3″ thick , with 0.5″ space between, to allow for drainage. my question is : should I cover the wood at the botom with : A) a plastic sheet ? B) paper barier like we use under the shingles on a roof ? C) or the landscaping fabric ? Of course for the A and B , I would make many holes to allow water to drain.
Thank you very much for your advise.
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We have a lot of slugs in our garden. We are building a raised bed and heard that lining the bottom with window screening is a good idea. I purchased fiberglass screening and now I am wondering if it will leech any chemicals harmful to vegetables, which is what we intend to grow in the bed.
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lars Reply:
June 1st, 2010 at 12:25 pm
@Anne
I personally would not worry much about it. There are plenty of fiberglass planters out there on the market, so I don’t see how the screening would be a very big deal.
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Hello – Is it necessary to remove grass before filling a raised bed with soil? Would it be OK to just cover it first with landscape fabric?
Thanks!
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lars Reply:
June 1st, 2010 at 12:24 pm
@Melissa
You can just cover it with landscape fabric, but the grass might figure out how to poke through. Particularly if it’s some kind of aggressive grass like Bermuda. You’d get the best results by taking a little bit of extra time and digging up the grass first.
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