How to Build an Herb Spiral With Old Bricks
Want to grow more herbs in a small space? Stack bricks or stones in an elevated spiral and fill it in with soil and compost. Plants like sage and rosemary that love dry soil go at the top, while herbs that like it cooler and moister go at the bottom. This DIY Herb Spiral project is from the book, A Woman’s Garden: Grow Beautiful Plants and Make Useful Things.
This page may contain affiliate links. As an Amazon Associate I earn from qualifying purchases.
One of the smartest ways to grow herbs is in an herb spiral. Situated in a sunny location close to your home, they create micro-climates that allow you to grow many herbs within the same small space. Typically made of bricks or stone, it winds up from the ground in a small spiral mound. Herbs that like more sun and drier feet get planted at the top. Plants that like moister soil and a little shade go towards the bottom. The sun also heats it through the day, releasing that warmth through the night.
My herb spiral is filled with thyme, sage, stevia, parsley, cilantro, summer savory, fennel, chives, and calendula flowers. Incredibly, and thanks to the design, all of those plants fit in an area that’s five-foot-wide and five-foot-long. When it comes to planting yours up, you can plant almost any herb in the DIY herb spiral. However, do avoid planting any belonging to the mint family. That includes lemon balm, peppermint, or spearmint, as they will quickly take over and choke out your other herbs.
A Smart Outdoor Herb Planter
When I first came across this outdoor herb garden idea, it was in permaculture literature. I then saw a couple of herb spirals in person when visiting other gardens. The idea is a practical and delightful way to grow a lot of herbs in a small area. As mentioned before, it also creates microclimates and also requires a lot less watering than herbs in containers. The design is such a clever idea that I had to build one for my home garden too. I also included plans and photos for how to build it in my new book, A Woman’s Garden Grow Beautiful Plants and Make Useful Things.
A Woman’s Garden is an introduction to eight categories of plants that we can use for natural dyeing, herbal medicine, handmade soap, and edibles such as culinary herbs. It includes gardening projects, crafts, and recipes that show how to grow and use some of the plants. The reason it got its title is that I’ve found that women are including more of these types of plants in their gardens. I wanted to highlight that, so I’ve featured eight gardeners and their growing spaces. They include gardeners who are also weavers, herbalists, and edible flower farmers. It’s a truly inspiring collection of gardeners (and plant-based makes!) to get your creative juices flowing.
Using Bricks to Build a Permaculture Herb Spiral
Looking online, you may come across herb spirals that people have built by mounding up the soil. When finished, some of them places stones on it to mimic a spiral. The issue with this is that it will create a low mound that could erode fairly quickly. The stones or bricks don’t stop rain from washing away the soil and are little more than decoration. My instructions below will show you how to build a more solid structure. One that will hold soil in place, and create a stable mound that’s able to retain warmth and give stability.
You can also build an herb spiral for practically nothing. You don’t need much in the way of equipment, and the bricks you use can be reclaimed. Using brick in the garden gives an attractive look, but you can often find bricks being given away. The ones you see in the photo above were given to me by a friend. If you’re not able to find bricks, or they are too expensive, you could use stones, seasoned wood, or a mixture of materials. Go for anything that’s non-toxic and that won’t affect your soil’s nutrient levels or pH too much.
How to Build an Herb Spiral
Equipment
- Spade
Materials
- 125-150 Standard-sized bricks
- Garden soil or topsoil
- Organic compost such as garden compost or aged manure,
- Herb plants
Instructions
- Find the best location for your herb spiral. It should be a convenient walk from your kitchen door, sunny, and, if possible, flat. If you build one on a small slope, level the ground before you begin.
- If the ground is clear of weeds and grass, you can begin building directly on the soil. If not, lay cardboard on the ground, covering everything growing.
- For the most efficient design, herb spirals should be 5-6½ feet (1.5-2 m) in diameter and 23-40” (60-100 cm) in height. If you live in a hot climate, make your spiral on the taller side since it will cast more shadow. The lowest end should be on the north side if you’re in the northern hemisphere and the south for the southern. That ensures that it gets a little more shade and moisture.
- Use bricks, or a sprinkling of flour, to create the outline of the design, ensuring the width of the growing area is at least twelve inches (30cm) wide.
- When you’re satisfied with the layout, begin building. Place a single layer of bricks on your design, then working from the beginning, skip 1½ or 2½ bricks in, and stack another layer, to the end. Keep repeating this until you’ve used up your supply, staggering the bricks to give the structure more strength. My spiral begins with a single brick at the lowest point and works up to seven in the center, but I’ve moved stones around differently to how you might do it. I also did a lot of adjustments at the end, moving bricks around until I was happy with how it looked.
- When you’re happy with yours too, fill the spiral with a 50-50 mix of soil and compost. I’ve used garden soil and composted horse manure in mine, but you could use garden compost, leaf mold, or another type of broken down organic matter to add moisture retention. The fill holds the spiral together, as will the eventual plant roots.
- When you’ve filled it to within a couple of inches (5 cm) from the top of the bricks, begin smoothing the soil. You want a gentle, downward slope spiraling from the top down.
- The last layer is the mulch. It can be anything from pure garden compost to straw but should be one to two inches (2.5-5 cm) thick on the surface of your spiral. Mulch keeps moisture in, excludes weeds, and if you’re using compost, it will also feed the soil and plant roots underneath.
- Water the spiral in, then plant your herbs in their respective micro-climates. Mediterranean herbs like thyme and rosemary at the top, and tender herbs like basil and parsley at the bottom. Plant them directly into the compost mulch, if you’ve used it, and give each plant the space it needs to grow. Water them in and keep the spiral watered regularly, especially during dry spells. Add a layer of compost to the spiral every year after.
Video
Notes
Planting the South Side of the Herb Spiral
One last thing I should mention. I planted the area in front of the south side of the herb spiral with flowers. This is the area where the bricks are getting quite tall, and the dwarf sunflower, dill, and chamomile I planted here appreciated the support and warmth. In front of them, I sprinkled a mix of dwarf (short-growing) wildflowers. I love the effect, and you can see how I used the chamomile from the herb spiral in this nourishing chamomile skin lotion recipe.
For even more creative ideas, check out the pieces below and A Woman’s Garden.
Do you need to line the interior so soil does not wash out when you water? How does that work to keep the soil in place with gaps between bricks?
Hi Mary, and no, you do not need to line the interior of the herb spiral. I haven’t seen any major issues with soil or compost eroding out of mine, so please don’t worry. Remember, though the bricks look like they have big gaps between them from the outside of the circle, they are nearly touching on the inside.
How much space is required for each type of herb? I am very excited to try to build this and grow my own herbs?
Thank you,
Judy.
Hi Judy, it really depends on the herb and also the variety of the herb you choose. A friend made this herb spiral last year and planted a small rosemary plant at the top. By this spring, the rosemary had swamped the herb spiral! Look at the circumference of the final plant sizes you’re choosing and work out how many you can plant inside. Choose smaller varieties, when possible :)
I look forward to making one in my garden but I was also wondering how you laid out the herbs. I have a few in pots now but since I now have the room for more I was looking for the best way to put them in the spiral.
When you plant your herb spiral, place herbs that prefer drier soil and more sun at the top. Plants that need more moisture and shade go towards the bottom. Don’t plant mint in it, or lemon balm or any other spreading mint-family plant. Otherwise they’ll take over. Have fun with your planting but also keep in mind the final sizes of the plants and try to give them enough room.
This looks so good! What a fun way to add an interesting landscaping piece and some useful herbs!