Raised garden beds are the perfect way to grow food in a backyard garden. I garden in raised beds for most of my garden, but when I built my garden, I made mistakes that have been haunting me for years. In this video, I share these mistakes so you can build a raised bed garden the right way the first time. Avoid a garden catastrophe: do not make these 3 raised bed mistakes like I did!
How To Build A Raised Bed Garden: https://youtu.be/VckmkIiwG3Y?si=Eu-lCU4ElpHOIm-s
How To Build A PVC Hoop House: https://youtu.be/81ri2YEBNZc?si=mX6daweKOo0tDo3x
Every Way To Install Drip Irrigation: https://youtube.com/playlist?list=PL1gY7BoYBGIHHHsx0JPcYgD4xXzA96usL&si=NTsuI7-ETlOSB3rI
How To Fill Raised Beds: https://youtu.be/GM77SCig22E?si=mhyjWlF4nRfaF7Xc
I use the following products* for gardening in raised beds:
Drip Line, 100FT: https://amzn.to/3IwqaKb
Thicker Row Cover, 1.5oz/yd, 10x30FT: https://amzn.to/45XW7Tj
White Insect Netting: https://amzn.to/40wJ5dE
Black Insect Netting: https://amzn.to/46HeJax
Shade Cloth (Many Sizes): https://amzn.to/49bqveh
PVC Snap Clamps (1/2 in.): https://amzn.to/4nvcGNn
Gorilla Carts Dump Cart: https://amzn.to/4noMiFg
Pruning Snips: https://amzn.to/4eZxCrM
Watering Wand: https://amzn.to/4lvOUiU
Weed Barrier (Many Sizes): https://amzn.to/4mj7nkl
Alaska Fish Fertilizer [5-1-1] (Gallon): https://amzn.to/4d9c1x7
True Organic All Purpose Fertilizer [5-4-5] (4lb): https://amzn.to/4mroKji
Espoma PlantTone Fertilizer [5-3-3] (36lb): https://amzn.to/4lgP9PW
Espoma PlantTone Fertilizer [5-3-3] (50lb): https://amzn.to/4lgPbr2
Espoma Bone Meal (10lb): https://amzn.to/4ieYapY
Azomite Trace Minerals (44lb): https://amzn.to/4eHwf24
Jack’s All Purpose [20-20-20] (1.5lb): https://amzn.to/4iRWtRc
Jack’s All Purpose [20-20-20] (25lb): https://amzn.to/3ZSJeGW
Surround WP Kaolin Clay: https://amzn.to/4jVhVDV
Pyrethrin Concentrate: https://amzn.to/42rnCCK
Spinosad Concentrate: https://amzn.to/460ZVoj
4 Gal Battery Backpack Sprayer: https://amzn.to/3HyCBUU
Full Amazon Store: https://www.amazon.com/shop/themillennialgardener
TABLE OF CONTENTS
0:00 How To Raised Bed Garden Intro
0:47 RAISED BED MISTAKE #1: DEPTH!
6:06 Ideal Raised Garden Bed Depth
8:06 RAISED BED MISTAKE #2: AISLES!
11:42 RAISED BED MISTAKE #3: INTERPLANTING!
16:51 Bonus Raised Bed Gardening Tips
20:21 Adventures With Dale
If you have any questions about how to raised garden bed design and avoiding raised bed gardening mistakes, want to learn more about growing fruit trees or the things I grow in my raised bed vegetable garden and edible landscaping food forest, are looking for more gardening tips and tricks and garden hacks, have questions about vegetable gardening and organic gardening in general, or want to share some DIY and “how to” garden tips and gardening hacks of your own, please ask in the Comments below!
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ABOUT MY GARDEN
Location: Southeastern NC, Brunswick County (Wilmington area)
34.1°N Latitude
Zone 8B
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#gardening #garden #raisedbedgarden #vegetablegardening #vegetablegarden
I built my raised garden bed seven years ago and before I started building it, I spent a lot of time planning and designing it. And because I did that, I did a lot of things right. But the mistakes I did make have been haunting me ever since. I have been working really hard over the last 2 years to try and correct those mistakes. And as I put in the work, all I can think to myself is, “Wow, I sure wish I didn’t make these mistakes in the first place.” Today, I’m going to share these hard learn mistakes with you because they’re not obvious. Hopefully, you can learn from my mistakes and not have to deal with this garden catastrophe like I now have to deal with. If you’re new to the channel, please subscribe, hit the bell for notifications, and check out my Amazon store and Spreadshop links in the video description for everything I use in my garden and awesome custom apparel and gear. Mistake number one is the mistake that has hurt my garden’s performance the most. And that is I made my raised garden beds too shallow. Now, full transparency, when I built this garden back in 2018, I had just purchased my new house, my first ever home, and I was broke as a joke. So, I went to the big box stores and I bought 2×8 lumber and I built as many affordable raised garden beds as I could. And I had to keep them shallow because I didn’t have the money to make them very deep. But what I didn’t know at the time is how much this would negatively impact the performance of my garden. To understand why this has hurt my garden’s performance so much, you must understand why we build raised bed gardens to begin with. There’s three primary reasons. Number one is to provide adequate drainage. Because if you live in an area that gets heavy rainfall and you grow in the soil and your soil doesn’t drain well or you have heavy clay soil, well, the plants may not thrive in that. But when you build up the soil into an artificial mound, it will drain better. So no matter what your climate, no matter what your location, you can have good drainage in your garden. Number two, it locks the soil and the nutrients in place. Here on the southeastern coast of North Carolina, we get torrential rains. In fact, we’re supposed to have a hurricane come within the next week or so. So, we could get anywhere from 5 to 12 ines of rain this week. So, if you live in a climate like this that gets torrential rain and you grow in ground, your garden can literally wash away. And the good thing about raised garden beds is it locks that soil into place. No matter how hard it rains, all of the water flows around the raised garden beds, protecting your soil and protecting your crops. And number three, it takes the native soil out of the equation. I live on basically beach sand here on the southeastern coast of North Carolina. It has pretty good drainage, but it is very poor in nutrients. Growing in raised garden beds allows me to control the soil that I’m growing in. So, I can use a very high quality, locallymade compost. I can amend it with organic fertilizers and I can protect and preserve that soil and also my native soil is heavy in root not nematodes so it doesn’t do well when I grow root not nematode susceptible plants in that native soil and the raised garden beds help protect against that but what I didn’t understand at the time is how demanding a garden bed full of annuals would be on that soil’s nutrient bank 2 by8s are only 7 and 1/4 in thick So, when you account for a mulch layer, well, you’re really only growing in 6 in of compost, and that just does not store enough nutrients, and it’s not enough highquality soil when you have a big garden bed full of large plants. They would do well initially when they were smaller, but once they started reaching their more mature size, they would demand more from the soil than I could give because they just weren’t deep enough. And even worse when root not nematode susceptible plants like tomatoes and peppers when their roots would tap into the native soil they would get root not nematode nodules and the plants would start becoming weak. So the only way you can get around these issues is to make your raised garden beds deeper from the get-go. Now thankfully this is a fixable problem. You can always build up your raised garden beds. And that’s what I’ve been doing over the last 2 years. I’ve been pulling up my existing raised garden beds and I’ve been double stacking them on top of each other to increase the depth more than double. And as a result, the plants that I’m growing in those deeper raised garden beds are doing so much better. These deeper raised garden beds are performing so much better than my originals, it is not even funny. And I attribute that to the much deeper soil. They can grow in a much larger, more controlled nutrient bank. And because I installed weed barrier underneath these brand new raised garden beds that I built, the roots can’t tap into the root not nematode laden native soil. So that’s blocking them. And as a result, I’m not having any issues with my plants in these garden beds so far having root not nematode damage. I think the results speak for themselves. I am having absolutely beautiful crops growing these deeper beds. I have tomato plants that have survived all the way until the middle of fall and they are over 12 feet tall and productivity is just off the charts. But the problem is it is a huge pain in the neck to turn my garden beds over because I can’t begin the process until nothing is growing inside the raised garden beds. So because I grow so actively in my garden, I always need a few raised garden beds that are empty and available. So, I have to wait until there’s at least two or three empty beds with nothing growing on in them for me to be able to pull one up and double stack another one. So, the progress has been very slow. And all I can think to myself is, wow, I should have done this right the first time instead of building a lot of beds out of 2x8s. I should have just built half the amount of beds, made them twice as deep, and then as money became more available, just add and expand my garden over time. That is the right way to do things. Build less beds, but build them right the first time. Don’t wait and have to improve upon them later. So, what is the ideal height for a raised garden bed? Well, I think for most gardeners, it’s going to be somewhere between 18 and 24 in. I think that is the ideal depth for a mixture of affordability and performance. These are all 18in raised garden beds. They’re double stack 2 by8s with a railing to sit on. And let me tell you, this is the perfect height for me to put your butt down. So, I really like these 18-in raised garden beds, but if you go up to 24 in and you get yourself a little bit more height, it will come at extra cost, but you’ll have to bend down less. If bending over is your biggest concern, you can go as deep as 32 to 36 in in depth. That will allow you to bend over less. But keep in mind, it’s going to displace the plants higher. So, while that may be okay for something like a pepper plant that’s not going to get super tall, this will work against you big time if you’re growing a tall plant like an indeterminate tomato. I mean, these things are starting at 18 in off the ground and just to get some kind of harvest up here. I would have to stand up on them. There’s no way I could reach to the top if there were any tomatoes up there. So, if you’re starting your tomatoes in a 32 or 36 in raised garden bed from the get- go, they may wind up being 12 to 15 ft tall by the end of the season. So, keep that in mind. You may be growing some crops that are out of reach. So, for that reason, it may be worth you having a mixture of various raised beds where some are middepth and some are taller for more reachable plants like lettuce or peppers or brassacas or things like that. But no matter what you decide, I’ll link to a video both above and down in the video description that will show you how to make this exact raised garden bed design. I think it is perfection. They are the best beds that I have ever gardened in. Now, this exact design makes an 18-in deep bed. But if you just want to make them taller, either use a wider piece of lumber or just stack up additional levels of lumber higher to achieve the desired depth that you wish. Raised bed garden mistake number two that I had to learn the hard way was making your aisles too small. This is truly the gardening mistake that has been haunting me since day one and I don’t have a way of fixing it. I’m just stuck living in this nightmare that I created for myself. When I built my garden back in 2018, I had three things on my mind. Efficiency, efficiency, and efficiency. I wanted to grow as much food in as small of a footprint as possible. So, as a result, I was as efficient with my raised bed spacing as possible. I put all of my raised beds with a 26-in wide aisle between them all. Why 26 in? Because I measured my lawn mower, and it was 25 in wide, and I wanted to have just enough space to push my lawn mower through to mow any grass or weeds in between the raised garden beds. This ultimately made no sense because I realized quickly that I was not going to mow in between my raised garden beds. it was too much of a pain. So, I just put weed barrier down in all of the aisles instead and I didn’t have to mow anymore. So, the whole reason why I chose that bed spacing of 26 in didn’t matter anymore because I never brought my lawn mower into my garden. Also, since those very lean days many years ago, I’ve accumulated a lot more gardening equipment and some nice stuff at that. some garden carts, some dump carts, wheelbarls, and I’d really like to be able to bring that stuff into my garden, but nothing fits. So, the whole reason why I chose this spacing, the lawn mower, I never used. And everything else that I want to use, I can’t bring into my garden. I have to do everything by hand because nothing fits except for me in these aisles. And unlike the height issue with my raised garden beds, this issue is totally not fixable. Yeah, it’s annoying to build up these existing raised garden beds and make them taller, but it’s totally doable. And it’s not that much amount of terrible work. But it’s impossible to respspace my raised garden beds once they’re already placed and filled. In order to give myself more spacing, I would have to stop growing in my entire garden. I’d have to remove all of the soil to somewhere else in my yard, then drag all of the raised garden beds back out and then re-space everything. It would take me years to do that. And in the meantime, I wouldn’t be able to grow anything. So, once you choose your raised garden bed spacing, you’re stuck with the aisle spacing that you chose forever. So, please heed my warning. Go with as much space in between your raised garden beds as you can possibly afford. I recommend at least 36 in spacing. That way you can get equipment in and out, fairly decent size equipment, and also move it and turn it around. But if you can go even wider, that’s even better. Just don’t stick yourself with these little narrow aisles that you can’t fit anything through or turn or make any pivots. Now, when I built these new raised garden beds last year, I did try to accommodate for this issue and spacing by giving myself more working room. But just to fill these raised garden beds with my dump cart, I had to take down this entire fence because I couldn’t get any of my dump carts or wheelbarls in through the gate of my garden. That is how much of a nightmare this has been. You have to take down the fence and then fill your beds and put it back up. Don’t do this to yourself. Give yourself more generous spacing from the get-go. It’s better to have a smaller, more usable space than a larger space to grow in that you can’t maneuver any equipment in or use efficiently. And the third raised garden bed mistake that I’ve had to learn the hard way over the years is not to interplant crops unless you are sure they are very compatible in their harvest window. The idea of interplanting many different species of plants within a single raised garden bed has become all the rage nowadays. They call it polyulture. But the truth is in most cases it causes more problems than you get benefits. That’s because the word polyulture is completely overstated in a backyard garden. Everybody’s backyard garden is already polyulture. It doesn’t matter if you’re only growing one single species of something in a single raised garden bed. you have other beds or other rows full of all different things. Monoculture is like when you take 20 acres and you plant nothing but apples or citrus on all of that 20 acres. A raised garden bed, even if you’re growing only onions in one bed and the next bed is only tomatoes and the next bed is only peppers, well, it’s still a poly culture because you have all of these different species of things growing right next to each other. You don’t have to necessarily have different species of plants all growing in one single bed. The problem with mixing different species of plants all in one single bed is they’re going to quit on you at different times and you’re going to have a very inefficient use of your garden bed space. For example, way back in April in this bed right here, I planted tomatoes, basil, cucumbers, squash, and melons. And since then, the squash and my initial planting of cucumbers and melons have all died. But I still have my basil growing, and I still have that giant tomato plant growing. So because of that, I have 50% of this raised garden bed completely going to waste where I can’t grow anything in it because half my stuff died, but half is still alive. I want to be able to grow things in a single raised garden bed where they all die at the same time so I’m able to turn over that bed and use it for another planting. I’ll give you another example. In this tray of seedlings right here, this is a mixture of broccoli, cauliflower, cabbage, and kale that I started from seed. Now, these are all brassacas. These are all closely related plants, and they do in theory make good companion plantings, but the problem is they all have very different harvest windows. Now, the old me would have just planted this all in one raised garden bed, but I would have created a huge problem for myself because the broccoli and the cauliflower, they they grow very quickly. They have a fast days to maturity. So, I would have harvested them probably by December. The cabbage takes a much longer time. they’re they won’t be ready for harvest until probably February or March. And then the kale, well, that’s a biianial that will grow all the way into the summer. So, if I mixed all of this stuff, I’d have a third of the bed open by Christmas with nothing I could do with the rest of that open space. Then I’d have the cabbage that are languishing for a few more months that maybe I’d be able to pick by Valentine’s Day. And then all of the locations that I put the kale in, well, they’re going to sit all the way into summer. So, I’m never going to be able to turn over that bed because there’s going to be stuff growing in it at different rates all throughout the year, and you wind up having a huge waste of space in your garden when you mix species like this that aren’t truly compatible in their harvest window. So, now I tried to keep my beds basically growing all the same things or things that have a very similar harvest window. For example, right here I have some onions and shallots that are decently far along and some brand new romaine lettuce transplants that I just put in. These romaine lettuce transplants are going to be done probably some point in early December and those onions are probably going to be done in December as well. So everything in here is going to finish up roughly at about the same time. And then once I pull all of those crops, since they’ll all come out at about the same time, I’ll be able to put down a couple of bags of compost, place a tarp over them, and then I’ll let that bed sit for another month or two for a fresh planting in late winter, early spring for whatever that crop will be. As another example, in this raised garden bed right here, I have a mixture of tomatoes, peppers, cucumbers, zucchini, and basil. This is a fall planting, something that I’m going to be picking in October and November up until frost. I would never plant a bed like this again in the spring because they would keep growing all throughout the season and I’d have half this bed occupied for the whole year and the other half I wouldn’t be able to do much with that space. But because this is a fall garden bed, everything is going to get killed all at the same time when we get hit by our first frost. So in this case, because the timing is different, all the things in this bed are going to turn over at the same time. And I’ve also learned to have dedicated smaller raised garden beds for things like kale because kale is a bianial. It’s going to grow all the way until June or July until all the brasa pests come and the pests kill my kale. If you don’t have brasa pests, they could grow into the next winter. That’s how longive they are. So I never interplant kale anymore. I want to give them a dedicated space so I can isolate them because they grow on a very unique timeline. They are not something you want to interplant with other things. But wait, I want to give you two more tips, and that is to add PVC hoops and drip irrigation to all of your raised garden beds from the beginning. Creating a microclimate for your plants by using a seasonally appropriate cover has been the biggest gamecher that I’ve had in my garden. When it comes to production, I like to use shade cloth over my PVC hoops in the dead of summer. I use this integrated shade cloth/insect netting in late summer, early fall when the sun starts cooling down a little bit. I’ll use a plain old white insect netting on the shoulder seasons to protect against insect pests. And then I’ll swap this out for a frost protective agricultural fabric row cover in the winter to protect my plants from the hard frosts forming on the foliage. Luckily, building these PVC hoops are incredibly easy. I will link to a video both above and down in the video description that will show you how to do that in only about 20 to 30 minutes with very basic parts. And all you have to do is get yourself some PVC clips and you can snap the covers right onto the hoops. And the other thing I’d recommend you do is to install a semi-permanent drip line in all of your raised garden beds. What I used to do was when I would transplant out my raised garden bed, I would run a drip line like you see right here and snake them through the rows as necessary. But then every time I would replant with a new crop, I would have to pull up that drip line and I’d have to realign it and it would get very annoying and sometimes I would have to add to it. But what I’m doing now is I’m installing six lanes of drip line with 6in emitter spacing in all of my raised garden beds because this is going to give me enough coverage no matter what I plant in this bed. So, I’m never going to have to pull it up or change the orientation. So, you can see all of the drip line I have installed here. This is going to be a semi-permanent installation. It’s going to stay in place for years until the emitters eventually clog. And usually I’ll be able to get 3 to 4 years out of the drip line before that happens. So that is going to be a heck of a lot easier than redoing it every 4 to 6 months when I put a new planting in the bed. If you want to learn how to install drip irrigation, I’ve made tons of drip irrigation tutorials over the years that will show you any way to install them, no matter what you desire. I’ll link to a playlist both above and down in the video description that will show you how. It is a huge gamecher. It’s the best thing I’ve done to my garden, aside from learning how to use proper covers over the plants based on the season. And those are my biggest raised garden bed mistakes that I made that I desperately wish I knew when I built my garden back in 2018. Please learn from these mistakes that I made. do these things the right way so you’re not dealing with years worth of problems and going through a catastrophic nightmare to try and pull everything up and redo things the right way you wish you did the first time like I am now. So everybody, I sure hope you found this video helpful. If you did, please make sure to hit that like button, subscribe to the channel, and please ring the notification bell so you’re notified when I release more videos like these. If you’re curious about any of the products that I use in real life in my garden, they are all linked in my Amazon storefront in the video description. So, expand the video description, click on the Amazon storefront link, and you’ll see everything I use in real life. And while you’re down there, please consider checking out my spreadshop for custom merch if you want to support my channel. I just released a whole bunch of new homemade custom designs. Thank you all so much for watching, and I hope to see all of you again on the next video. Today was Costco day, so that could only mean one thing. It’s rotisserie chicken day and that means there is a Dale stalking our dinner. Dale is being a very good boy. So, we’re going to give him a nice white meat piece of chimpin. Gentle. Oh, he’s drooling. Oh boy. Oh boy. That was aggressive. Okay, I’ll give you one little piece of dark meat, but then after that, that’s it. Okay. Be gentle. Gentle. Okay, buddy. Now I want you to go on your bed. Come on. On your bed, Dale. Come on. On your bed. Away with thee. I’ll give you a piece later. I’ll give you a piece later. Come on. Come on. Later, buddy. I promise.

23 Comments
If you enjoyed this video, please LIKE it and leave a comment! Thanks for watching 🙂 TIMESTAMPS here:
0:00 How To Raised Bed Garden Intro
0:47 RAISED BED MISTAKE #1: DEPTH!
6:06 Ideal Raised Garden Bed Depth
8:06 RAISED BED MISTAKE #2: AISLES!
11:42 RAISED BED MISTAKE #3: INTERPLANTING!
16:51 Bonus Raised Bed Gardening Tips
20:21 Adventures With Dale
To make my raised beds I used regular lumber 2”x 8” x 10” boards and nailed a 2”x 2” x 10” piece of lumber in the corners. They sit on the ground. Then I place a double layer of corrugated cardboard onto the ground and add soil on top of it to fill the bed. Top dress with compost when planting. The lumber is still perfectly functional 5 years later. Zone 2b-3a Sk. Canada. Happy gardening!
I saw " The Bob"…..
Never. Always. Impossible.
Not really….
But good points!
my granddaughter has a" lil red wagon"…..she will help u with the dirt!
Live in Wilmington also, do you know anybody that could build a bed for me like you’ve described?
Good info, especially how wide your walk ways should be.
Went with metal beds a few years ago – 8'L x 3'W x 2'H – working great and saves my back! And no worries about rot.
I like using concrete blocks for my raised bed
Raised bed – 14" to 24". There's a lot of shallow rooted vegys we grow where if the plant is given the space for the roots to spread out which is what those types of plants want to do they'll do great. Lettuce is a good example. I raise lettuce in grow bags that has 12" of soil and they do fine. The bigger issue is me giving them the space to grow out when they mature and not overcrowd them, and this is also the issue for the root system too, as the roots will want to spread out more. You can take the soil level almost to the top and have a thin layer of mulch of a 14" bed and you're fine with a lot of vegys.
I don't care for the lip at the top. It serves no purpose for me since I don't sit on the edge of a raised bed. It's more effort to make the raised bed and more cost.
Anyway those are the most common recommendations with a handful of exceptions that go 24 – 36" such as watermelon, pumpkin and a handful of other deep rooting crops, or perennials like asparagus. Best to look at a root depth chart before making your beds and make sure you're deep enough.
Yeah, make sure a good wheelbarrow fits between the beds. I use 32" for the isles and even with that I feel a little crowded but it's enough to get my wheelbarrow through so I'm OK. If growing tomatoes make sure your step ladder will fit.
I made the same mistake as you. And I did build my garden bed deeper with wood and everything going good for about 4 years all the wood framing went bad! So this time I used cinder block. I wish I use cinder block at the beginning.
Some plants need more root depth. So 18” will limit the growth of some plants. A potential solution to the width issue is to sacrifice the width of some of the beds. Reducing every other bed by 1’ or 1.5’ would widen your space between the beds. You would still have a bed there just a more narrow one.
I think if you have the space you should go bigger than 48" wide. A skid is 48". So a little bigger you can use skids for harvest ect…
Farmers in California leave crop areas "rest" for a season every other year.
Or just remove a row or two raised beds….permanently. gradually as you pull up the raised beds to double the height or whatever, move them over and increase spacing. It may take a few years, but better to do it while you're young enough to manage it. You may need those wheel barrows as you age.
I have been watching your videos but haven’t started any raised beds yet. I am learning SO much from you. Thank you for sharing ALL your knowledge. Also, you can tell everything you need to know about a man by how he talks to and treats his dog. 💙
What kind of wood are you using? Treated? Cedar?
You didn't mention end of bed spacing. I get that extra spacing between the beds is useful, but can make some of that up by eliminating end of bed spacing?
East TX here love your beds I had wooden beds that I built I miss them however I learned in my area that’s got 2 rainy seasons and the way my land is the water RULES and my hard work went to BEND AND WARPING in 2yrs
So now that you have recovered, add a layer double
My beds do perfectly well in 12 inch high beds.
Also, I have grass in between my beds. My mower is 21 inches wide. My aisles are about 36 to 38 inches wide.
I would definitely start changing the aisle spacing, no matter how much work that is. If there is one thing I have learned in life, if something bugs you, fix it ASAP. Get things the way you want them, it spares you the daily small irritations!
Seems to me that if your raised beds are bottomless that eventually the soil under you beds would become conditioned from absorbing the nutrients from above it.
I have also added height to some of my beds by just digging out the four corners, placing a 18” 4×4 in each corner and screwing in to it.