Raised garden beds are a great option for gardening. Gardens are a great idea but if you are not sure how to keep the plants from invading each other or do not trust the soil already in your yard, purchasing garden beds might be a good idea. But then there is the issue of plants growing too tall and blocking out sunlight for any smaller plants.
How much space do you need between raised beds? Raised beds should have at least 2 to 4 feet of space between them, especially if you plan to walk through the raised garden to get to other plants in the garden. You do not want to mistakenly step inside of a garden bed while trying to keep out of another.
No matter your reason for using them, whether it is to make your yard look plentiful and so you can grow your own fresh produce, or what kind of plants you are putting inside of them—they will all require the same thoughts before you go out and buy them.
Measurements
For the sake of understanding, I am going to speak with a traditional garden in mind since the raised beds along the kitchen windows do not require as much thought except to make sure that they are properly supported and do not contain a mix of plants that are both invasive and equally require full sunlight.
Keeping accessibility in mind is key to planting and good gardening. You want to be able to tend to your garden as often as they demand without getting in the way of any other vegetation. And also, to keep other people from accidentally smashing them.
Plants that take root too close together may end up competing for the water, sun, and other nutrients in the soil. You want plants to have the capacity to grow to their full potential with the least amount of inhibitions. Take note on how to separate the plants and then separate the beds.
Spacing
Depending on how the garden is laid out and where—you will need to create pathways for easy access through the dirt and to other plants. The paths should have more space between the beds than any other bed. If you have not thought about creating an actual stone pathway, you might want to. But if not, an extra foot of space between the beds should do the trick.
Consider who might be using the path, how many, or how often—that can also help determine how much space will be necessary. Constant traffic back and forth will eventually wear down the top layer of the soil, and fresh soil will get packed in. You want to be confident that your plants will not end up under the feet of anyone and nor will its surrounding soil.
That is another reason to think about getting stepping stones or a little road path throughout, especially if it is a rather big garden meant to be appreciated by guests. In other words, two people should be able to walk side by side through the garden without trampling over any precious flower or herb.
Length
This is not as relevant as the other dimensions. The length of the bed depends on what you want in your garden, how much of a plant you are going to put in it and where exactly you are going to put it. However, the longer the bed, the more cross supports will be necessary to ensure the sturdiness of the structure.
Width
The width is probably the most important dimensional attribute. You do not want to have your feet too close to the plant or inside the bed at all, really. The beds should be between 3 to 4 feet wide to provide enough working space for you or admiration space for children. If you can only get to the bed from one side, then keep it at 3.
If you are growing vegetables then you will most likely need to reference a size chart. Since the roots of a veggie will determine how big it will grow to be, you want to give it enough room to take root as far as it possibly can without getting into competition with other roots close by.
Height
The tallest bed you will see is about 36 inches, and the shortest will probably be 12 inches. The height is really what determines how much new soil will be needed. If the soil you are putting the bed into is not very good soil, a taller bed will suit better so the plants are able to take root in the newer soil that you put in. Plants require no less than 10 inches of accessible soil to take proper root.
The taller the height, the more support the bed will need to make sure the sides of the bed do not falter. You have to remember that the beds are not just enduring the heaviness of the soil, but also the water that the soil will absorb even as the bottom allows the water to filter out.
Other Factors
Besides the dimensions, these are things you should also take into account before going out and buying a raised bed in the first place. These will determine what you have the space for and which spot has the capacity of taking better care of the plant when you are not actively tending to them, how to keep unwanted guests out and how to reach it with bulkier tools.
Location
Which plants are estimated to become the tallest, and which plants are going to need the most sunlight? A plant that is going to be short but needs full sunlight should not be planted in the same box or even close to a plant that is going to completely tower over it. It might be smart to put the shortest closest to the pathway and keep the taller ones in the back.
If you have a veggie garden, most, if not all, of what you plant will need at least 8 hours of direct sunlight a day. Anything less with result in a small veggie or a dead one. If you have a garden mixed with veggies, herbs, and ornamentals, you should designate them to individual sections of the garden.
Pest and Weed Control
By using a raised bed, you are already blocking off partial weed access, and the walls allow most animals to keep at bay, but this also depends on how deep you dig the bed into the soil. Even if you make the rim of the raised beds only partially visible, it would be wise to place weed barrier fabric and/ or hardware cloth underneath to keep both plant-eating creatures and annoying weeds from invading.
Using Large Tools and Appliances
Do you need a lawnmower to reach the grass close by or a wheel barrel to reach the uninhabited soil behind already established green to plant more? This goes along with spacing—think ahead of how much room you will need to guide the larger gardening tools. Or even if the weeds that tend to attack are the kind that only a weed whacker can solve.
You do not want loose weed heads flying into other sections of the gardens. That would defeat the purpose of installing a weed barrier in the first place. Leaf blowers, too if you have a tree in the area and do not want the fallen leaves to block the rain from reaching the soil around the roots or the sunlight from reaching the plant. Plus, most leaf blowers have a lot of power and are capable of also blowing away the dirt around the roots.