If you don’t have a lot of space to make a garden this year, or if you simply are looking for an easier way to create a garden at your home, you might want to consider a planter box.
You can buy planter boxes that are already made, of course, both online and from local retailers, or you can build your own. There are plenty of plans and directions online!
Before you start this process, however, you have to answer one very important question: how deep does a planter box need to be for vegetables? Let’s find out!
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How Deeps Should You Go?
How deep your planter box needs to be depends greatly on what you are planting. At a minimum, you need to make sure that your planter box is at least a foot deep. Depending on some of the plants, however, you might want one that is a minimum of two feet.
Let’s look at veggies and herbs like radishes, parsley, spinach, corn, onions, or lettuce, you only need a planter box that is about 12-inches deep.
Other vegetables, such as tomatoes, peppers, eggplants, or carrots need to be planted in a planter box that is at least 18-inches deep.
Finally, we have the plants that need a bit more space in a planter box that is at least 24-inches deep. Vegetables like potatoes, asparagus, and artichokes should be planted in these deep boxes.
Let’s Talk About Soil for Your Planter Box
Now that you know how deep your planter box should be, it’s important to talk about soil. You should make sure to choose good-quality soil, of course, and it’s important that you don’t overfill or not fill enough.
Generally, you have chosen the depth of your planter box based on the type of vegetables you want to plant. So, fill that up! Ideally, you should leave 1-2-inches of space from the top, but the rest of the planter box should be filled.
Everyone fills their planter boxes with soil at the start of the season, but it’s also important to refill it with soil as needed. This not only gives your vegetables room to grow, it also refreshes nutrients in the soil.
What if you don’t have enough space to have a deep planter box? It’s okay! You can still grow some vegetables and herbs in planter boxes that are as small as 6-inches deep. These options might include radish, spinach, onions, lettuce, and garlic.
Is Depth Extremely Important?
Yes, the depth of your planter box is important. Vegetables require enough room to grow to their full size, and if they don’t have this room, they could be stunted. Remember, both the roots and the leaves of the veggies have to have space to grow.
If the plants cannot grow enough, or to their full size, your harvest will not be as productive. You might notice that your vegetables are struggling, or they might only put out a couple of fruits instead of many more.
Another issue with a planter box that is too small is that the roots of the plants can become restricted. Leaves might begin to turn yellow, and eventually die off because the roots are not getting enough nitrogen. This is essential for strong growth.
Planter Boxes – Bottom or Not?
Some people wonder if they need a planter box with a bottom or if they can simply put the box directly on the ground. You can do either, of course, but it might be better to keep it bottomless.
Why should you consider a bottomless planter box? Well, it’s so the box has better drainage. If you have a bottom to the planter box, you might find that the soil gets too wet, which can damage the roots.
Additionally, when the planter box sits directly on the ground, you get the benefits of nature’s goodies, including fungi, worms, and good bacteria. This keeps your soil and plants healthy.
If you have to have a bottom, that’s okay, too. You can layer your planter box with pebbles and sand, along with the soil, and that will help with drainage. As long as your planter box is at least 20-inches deep, you shouldn’t have issue with doing this.
Growing Tips for Planter Box Vegetables
Now that you know how deep to create your planter box, you might be interested in knowing more about how to be a success with this type of garden. So, here are some tips to help you to succeed:
Use a High-Quality Soil Mix
It’s very important to fill your planter box with the best mix of soil for whatever it is that you are growing. Some garden centers, and of course online resources, have soil that is specific to your box.
For instance, you might go to your local garden center and see soil that says, “tomato soil mix”. This would be perfect for your planter box if you are planting tomatoes or similar vegetables, like peppers.
If you see a soil mix for succulents, however, this would not be a good mix for your planter box. The soil you choose will have a direct impact on the outcome you have.
Another option is to make your own soil. There are plenty of resources online that tell you how to make mixes of soils, clay, sand, and perlite to create the perfect soil for what you are planting.
Don’t Forget to Water
You also want to remember that you don’t want to forget to water your planter box. Watering is very important to growing plants, and they must have enough to thrive. You can use a watering can or a hose.
How do you know if your plants need water? They might look wilted, or they might start to droop. You can also test the soil with your fingers. If you can stick your finger into the soil for more than an inch and still feel dryness, you should water.
It is also important to water your planter box if you have had a few hot, sunny days in a row.
Fertilize The Planter Box, Too
The last thing you want to remember when using a planter box for your garden is that you want to fertilize it. Most fertilizers are applied monthly. It depends, however, on what type of fertilizer you choose.
Choosing to use a planter box for your vegetables is a choice that will bring you a lot of joy. You can grow wonderful vegetables in these, and it is a relatively small investment. Start now, and choose wisely, and you will be marveled to see the great harvest you get in a few months.