Are Raised Beds a Good Idea?

Raised bed fail. Our appalling parkway beds. Extra demerits for having used treated lumber! *

Raised beds have some pluses and minuses. Lately I’ve been thinking about their drawbacks. Namely:

  • Cost
  • How fast they dry out in a hot climate.

Now I can also think of a few reasons one might want to grow vegetables in a raised bed:

  • You do a soil test (and you should do a soil test, especially if you live in an urban area) and the results come back showing that you have heavy metals in your soil.
  • You live in a very wet climate.
  • A disability prevents you from kneeling or leaning over to garden.
  • Your soil has no contaminants, but has some other problem, say bad texture or lots of buried rocks/chunks of concrete.
  • You have dogs/rabbits/chupacabras, etc. 

I’ve come to the conclusion that for Southern California and, by extension, any dry climate, raised beds are a bad idea unless, of course, you have any of the issues mentioned above. Particularly in the summer, the raised beds I have in the parkway, pictured above, have performed poorly. So poorly, that I’m going to remove them soon. If a soil test shows high heavy metal levels I’ll just go with some ornamental/insectary plants.

 Above, broom corn (Sorghum bicolor) doing just fine straight in the ground.

A partially sunken bed. Extra points for finding the stinkhorn mushroom.

This bed is somewhat of a compromise. I cut the bed in half lengthwise to make it half as tall as it used to be thus getting two beds for the price of one. Then I sunk it into the ground In effect, the veggies are in the ground but I still have the neatness and defined borders of a raised bed.

Again, if you’re in Seattle raised beds are probably a good idea. But here in SoCal, I’m going to skip them from now on if just because of how much water they waste.

*ETA: A note from Mrs. Homegrown re: that topmost picture of the sad, sad raised beds. They look terrible because after a couple of seasons of struggling with mysteriously declining crops within their borders, we’ve given up on them and did not plant them this spring. I don’t want anybody thinking they look so poorly *only* because they are raised beds. That pair of beds has produced very well in the past, but has some sort of soil problem now–one which we can’t figure out. So I wouldn’t agree with labeling the picture “raised bed fail”– it’s more of a gardener fail. It may have something to do with the fact that they are raised, that the soil texture has deteriorated over time due to the elevation–that is Erik’s theory. I’m not so sure that’s all that is going on. Nonetheless, I do agree with the overall point of this post: that in this climate sunken beds make a lot of sense.

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44 Comments

  1. Yes- I totally agree with this. Our beds are all raised- clay soil. I can’t believe the amount of water I have to use. Even with heavy mulching. It’s just waaaay too hot here in central Texas.

  2. We live on a steep hill and our soil is heavy, compacted clay. Because it’s a hill it’s good that it’s compacted. We want it to stay on the hill and not visit us on the patio.

    So I’m thinking of some kind of happy medium – framed boxes with extensions for trellises, fencing to keep out critters, and shade cloth – sunk into the ground and filled with better soil. The plants start growing in the crack soil, and then send their roots down into the heavier clay.

    At least that’s the idea. I’m not sure if it will work. It’s been a challenging season.

  3. I love my raised beds. Number one most important fact would be to fill them with the very best growing medium you can find. Number two would be to install some sort of watering system…I use a s-l-o-w soaker hose…one gallon an hour. I also swear by worm castings and compost tea. My raised beds are cinder blocks. I also garden the *regular* way…for corn, squash, and melons…my tomatoes are grown in bottomless five gallon buckets. I think the BEST way to garden would be to utilize more than one gardening style.

  4. Here is South Texas, although we normally have a wet season, there are looong stretches of very dry very hot weather. You are absolutely right – raised beds don’t cut it in this climate. Unfortunately most gardening books are written by people who don’t live in the South and have plenty of rain. So all of us who live in hot dry places are initially fooled into thinking that raised beds are the way to go (just like after reading so much about passive solar greenhouses I convinced myself they’d work in this climate. Ha!). People always think I have raised beds because mine are surrounded by old fence boards but really, those are just mulch containers. The soil is at ground level but I maintain at least 6 inches of leaves or straw. A mulch that deep really really helps keep the moisture in and I can only keep it in place with a “raised bed”.

  5. I think there are a lot of ways to do raised beds, and that the one that you demonstrate on your parkway wasn’t particularly effective. I can’t tell if the parkway beds are over soil or over concrete. When I’ve done raised beds that aren’t over the top of soil, I’ve tended to make them much, much deeper–at least 1 foot, preferably 18″ deep, although naturally, YMMV. Or maybe I’m misinterpreting what’s going on in the pictures?

  6. I abandoned in ground this year in favor of all raised beds. I live in the San Joaquin Valley. We sell our water to Los Angeles, so we have to pay more for our own water. The way I have handled the cost is to bury two liter bottles upside down, halfway in the ground next to each plant, having cut the bottoms off the bottles and pierced the caps with a hot skewer for slow release. I am targeting the root systems. So far, I have had much success.

  7. I’m having great success with my raised bed veggie gardens – I’m using Mel Bartholemew’s Square Foot Gardening mix in them. I think it’s important that your raised bed soil has water retaining properties – and mine has coconut husks in it, which really retain water (peat moss alternative). Also, mulch, mulch mulch!!

  8. I live in North Carolina and my soil is thick, heavy red clay with extremely poor drainage (especially with all of our summer thunderstorm activity). The cedar I used for my beds was expensive, but worth it in the end.

  9. Here in Massachusetts we have a few raised beds for neatness and prettiness, and also as terracing on a bit of slope. In most of the garden we use mounded raised beds, about three inches high, as recommended by The New Victory Garden. Again, it’s mainly for neatness and to delineate what’s supposed to be beds and what’s supposed to be paths.

  10. I havent had any problems with our raised beds. In act I prefer them to the actual ground since I have a lot less weeding to do with a raised bed. A soaker hose has been a godsend in our raised beds and we save a ton of watering money this way (and time watering too since I have them on timers). Im actually pulling up my 3 remaining raised beds (each about 4’x10′) and moving to all wine barrels… I know I’ll have a lot of extra primo soil after transferring.

  11. I was trying to find some pictures but in traditional Islamic gardens, which are in hot and dry countries, they have sunken beds and the irrigation channels are raised. It might work for you. Short rain showers certainly soak in.

  12. We don’t use raised beds at Winnetka Farms for the one reason they limit our ability to work all the soil area. One season an area is a pathway the next it’s growing peppers. In the 6000sq ft that most of the vegetables are grown there are only two permanent pathways that divide the total into 4 sections, all other paths are rotated seasonally. I also never walk directly on bare soil, only on designated paths covered with straw, otherwise it’s like walking across your dinner plate.

  13. I live in hot and dry South Texas and use raised beds with drip irrigation and lots of mulch. Most of my raised beds are bordered with concrete blocks, but others are made of wood. The soil here is rock-hard and terribly infiltrated with Johnson grass. In addition, the drainage is bad…when it actually does rain heavily (rare but it does happen) the water just sits and the plants not in raised beds die—tomatoes, peppers, squash, etc. So, raised beds help me to address 1) the rock-hard soil, 2) the Johnson grass, 3) the bad drainage. I’ve tried vegetable gardening with and without raised beds, and would not do without the raised beds.

  14. Cost is nonexistant if you use found materials but if water was a factor for us I’d rethink their use. BTW, did you sautee that mushroom or use it fresh ?

  15. In our community, we have raised garden beds for rent for a modest fee (includes water). The beds are created out of cinder block, several feet tall.

    We’re in the desert southwest- the beds work if shade cloth is used for certain plants and also if the correct plants are chosen- some gardeners are having great success with tepary beans and others from Native Seed Search that are adapted to our arid climate.

  16. My picnic table /was/is treated lumber. Everything under it died and will not come back. Other tables must be moved to mow or either a weed eater has to be used. I got a new picnic table with the new treatment. The table is painted and sits on bricks and in a slightly different position. It is still killing grass and weeds.For my one raised bed, I bought untreated lumber and painted it. Termites like the unpainted part. Even with cardboard, lots of layers of paper, water, and composted kitchen manure and chickens scratching in it, weeds still managed to come up inside the edges. I would lay your failure as much to the treated lumber as to raised beds or the climate. You can see my little raised bed on my blog when I post tonight. Of course, I live in a rainforest aka The South, so getting too dry is not as big a problem here. If you use cedar or treat regular wood with some sort of oil, that is supposed to help the rot issue and keeping it from drying out. I would not eat anything from a bed of treated wood. Of course, no telling what store-bought food has been grown in or around. It is a wasteland where the old picnice table was and where the new one is, both of treated wood.

  17. They’re also beneficial in cold climates or for early crops when you’re waiting impatiently for the soil to warm up.

  18. You could have wicking beds in a hot climate. That’s what I’m in the process of doing. That way you don’t have to worry about them drying out (as much).

  19. I am with you here.
    Our experience in Denver was that while a neatly defined border was helpful anything else was a waste. Combined with the no till heresy outlined but not raised beds produced our consistent best results.
    I also wonder if just a very slight elevation would help in super wet (pacific northwest) environments as well.

  20. I think raised beds are thoroughly overused. For the majority of people there’s perfectly good dirt under their feet and all they need is a shovel and a few packets of seeds to get started.

  21. One other benefit that I get from my raised beds is protection from gophers. I have hardware cloth on the bottom to keep them out. I haven’t found any other dependable way to deter the gophers.

  22. I cram as much vegetation as I can into my raised beds.. the plants shade the soil nicely enough that it doesn’t dry out too much! But it’s true, I probably do use much more water on them then most people would on their vege. Shorter showers it is….

  23. Funny you mention it, I’ve been reading an essay by one of the people at a local urban farm – about modified raised beds using lots and lots of wood chips: http://fullcirclesunnyvale.org/fcfwordpress/wp-content/uploads/2011/02/MRBS-Ramial-Wood-Chips-V.62.pdf

    Basically if you have the human-power, you can mound up the soil into rows, cover -everything- in several inches of wood chips, and plant away. I will note that Full Circle Farm has a significant gopher problem, but they manage it pretty well with trapping.

  24. Hi from Seattle: we’re partial to mounded beds (no wood edges), click the name link to see more. In our entirely unscientific experiment this summer, our lettuce from the one raised bed (actually a cold frame) has snails in it and is getting eaten, while the lettuce from our mound beds is pretty much snail free. The wood sides give the snails and slugs a place to hide.

  25. Even here in Seattle we need to water on HOT days, potted plants need water twice a day. The best soil isn’t even going to help. Something needs to be added that will hold water – compost is good. Mulch! is very important. And we alway got tons of slugs in our mounded beds. My husband went slug hunting every night with a flashlight going from 67 slugs to 10 slugs a week later. Also try dried and crushed eggshells, OUCH! also sand sprinkled over bed. This was never hours of work but a little bit every day. We managed not to lose much. I know there is a lot of advice out there but this worked for us.

  26. Hi
    Have you thought of using wicking beds. They are a raised bed with water storage under. I use them in hot dry Australia and I use far less water than my other garden beds.

  27. Here in NY, I love my raised beds with wood sides. But we get upwards of 40 in. of precip annually and my soil is pretty much clay. So creating a raised bed of 6 – 10 inches works well. In a dry summer I do think they dry out faster though. This past spring was VERY wet – we had 8″ of rain (normal is 3.5″). I was only about 3 weeks late putting in the early stuff (peas, lettuce, etc.) while those gardening on the ground were still waiting for the soil to dry out weeks after that. I notice local corn fields are way behind – around here, corn is supposed to be “knee-high by the 4th of July” and it was not. As for treated lumber, I think there’s a lot more fear of it than is warranted. I researched it pretty thoroughly, found several excellent articles (especially some in Fine Gardening magazine) and the evidence for avoiding it just isn’t that compelling. And, if you use regular lumber, especially in our wettish climate, you’re going to be replacing it twice as often – i.e. cutting down more trees. Certainly, if you want to market your produce as organic you shouldn’t use treated lumber, but otherwise I don’t think it’s quite the issue people make it out to be. Either way, wood sides also let you easily attach wood uprights as well – for things like super tomato cages, and other supports. I always use screws so I can move the supports to a different bed next year. I do not use any kind of corner posts on my wood beds. They “float” on top of the ground and have never been noticeably affected by winter heaving or anything like that. I use 2-by lumber and just screw the ends across the sides with 2-1/2″ deck screws. That way I can easily take them apart if I want to move things.

  28. ===I have a modified raised bed as a test (sandy soil)

    ===Some of my best plants are doing very well there without extra irrigation, due to using this technique:

    http://www.richsoil.com/hugelkultur/

    ===The slow-rotting wood definitely acts as a sponge, and makes it so I can get more mileage out of my water resources….I will definitely be doing more of this.

  29. Sorry for the long comment, but wanted to share an experience:

    I agree that raised beds have are not, in most cases beneficial for soil or water here in LA (although for some people or sites there are advantages).

    However, I jumped on the sunken bed bandwagon a few years ago, and after digging a number of them, think that they are not really worth it in many cases either. The earth moving is a ton of effort, and we don’t get the summer thunderstorms that may make the overland water flow harvesting worth it in the Southwest areas that do.

    A happy compromise that has worked well for me in the past when I am watering with a plain old hose has been normal in ground beds surrounded by small berms that hold water in, and provide a bit of shade for young plants. Berms can be planted with small herbs and other plants to attract beneficial insects and pollinators and distract pests with strong scents. From the path, I had to reach a bit farther to get to my plants, but I also put in a few stepping stones in the beds to increase access.

    While there were some advantages to this, and I may try it again, I’m not totally convinced that there the advantages are worth the extra effort vs. a regular in ground bed with good soil that can absorb and hold water.

  30. Don’t know if it’s been mentioned, because I’m late to this party, but you could try solarizing the soil in the beds with some clear plastic for the summer, and then plant them up for a fall/winter garden…

  31. I like raised beds, intensively planted, with special soil with added moisture retention elements. Have you considered using Ollas, I’ve had a good experience with them. The punctured pop bottles get water to the plants slowly, but the advantage of Ollas is that the roots literally wrap themselves around the Terra Cotta.

  32. This morning I planted a bed that I prepared last Fall. I’d mixed amendment into the soil and it was all set to plant. The only reason I waited until now was because of the baby skunks inhabiting our yard that consider my bed their playpen.

    The bed has been watered over the year as it’s sandwiched in between two other beds. Here’s what happened. It seems that when wet, the heavier clay in my soil sunk to the bottom of the bed and the lighter amendment floated to the top. They separated and all my work blending the amendment into the soil was for naught. When I scraped back the moist amendment there was bone dry talcum powderish compacted clay underneath – laughing at me, I might add.

    Permaculture is supposed to be about not making work for ourselves and I’m working too hard. It’s also supposed to be about observing our situation. My clay soil does not want to be amended. I think I’m going to listen. Raised beds may not be the complete answer but I’m going to have to find some sort of compromise solution.

  33. For my first garden this year in Tulsa, OK I opted for a bucket garden. It’s comprised entirely of freely obtained food grade buckets…many of them I made I to sub irrigated planters or SIPs. I live in an apartment and garden in a friend’s backyard on his unused driveway.

    The heat has been BRUTAL this summer in Oklahoma and I’ve seen and heard about a lot of traditional in ground gardens failing from the super dry conditions. It’s mosty been a big success. It doesn’t require as much watering, is inconvenient for a lot of critters and I haven’t really had to weed at all. And obviously you can just move the plants around throughout the season to adjust to heat and light conditions.

    Here is a recent post about it on gardenweb and a link to the photo set on flickr:

    http://forums.gardenweb.com/forums/load/okgard/msg0717273930107.html?6

    http://www.flickr.com/photos/bumcrush/sets/72157626911478230/

  34. ..I like our raised bed. We created them to save time and learn..they do dry out fast though. Now that we have been doing raised beds for 3 years we might move to a large garden next year. time permitting!

  35. My raised bed produces better looking and producing plants than what I grow in the ground by a mile. All New Square Foot Garden method makes the difference. They don’t dry out, you can’t overwater, you don’t have to double dig, you can put them at waist level if you’d like…so many advantages.

  36. Can anyone recommend a good beginner’s book on planting things together? I have Giai’s Garden (which is great for the big picture of how your whole landscape can work together), Pat Welsh’s Southern California Organic Gardening (a perfectly brilliant overview of the year in this climate), and Gayla Trail’s Grow Great Grub (which I refer to for information regarding plants individually, but since it’s intended for growing food in pots there isn’t anything really on how to compose a 4 by 8 raised bed). I just need to see a sample layout or two. Right now, trying to pull together individual descriptions and seed packet info has me overwhelmed and banging my head on what is probably a pointless exercise of reinventing the wheel. Just some kind of “orient your bed North South. Run an 8 foot trellis down the middle of the bed for 1 pole bean plant, 1 cucumber plant, and 2 indeterminate tomato plants. On the East side of the trellis so that they’ll be shaded from the hot afternoon sun, plant mesclun and alpine strawberries. On the West side plant 2 bush beans, 1 pepper bush, basil, and New Zealand Spinach.” :p I also (it may be obvious) don’t yet have a sense of how much you can fit in one bed. In a year or two, I can probably wing it but if there’s a book out there, I’d love to get it. Thank you

  37. Hi Joss,

    There’s no right way to lay out a bed. I just ask myself how much of any particular crop I want to eat and plant accordingly in blocks using John Jeavon’s biointensive planting. I have friends who just throw seeds around and see what comes up. Both approaches work fine. But this is a big topic–I’ll do a blog post or a podcast about it soon.

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