You may ask why would you want to make a spiral herb garden rather than planting your herbs in a normal garden bed. One answer is that the spiral design looks attractive and it certainly does, but that is not the only reason. Because the design winds up to a high point at the center the soil conditions vary throughout which will suit the requirements of the different herbs. All this is explained in an article I found on the Balcony Garden Web site.

Learn how to build a herb spiral in this article. A spiral herb garden is used for growing different herbs in a small space. With it, you can make a perfect use of your vertical space in an arranged manner.

A herb spiral is basically a small herb garden. It is three-dimensional and have beds in a confined, sloppy space of spiral shape, which can be used to grow various herbs. The top area of the spiral receives the full sun and has superior drainage, therefore, herbs that like exposure to the?sun and good drainage are planted there. The bottom area of the spiral is suitable to grow herbs that require moist soil and less sun.
Herb spiral has spirally upward walls that are made of natural stones or bricks. The spiral shape is enlarged in contrast to the raised bed, the bed area has sufficient space to grow herbs and there are several zones with different soil characteristics and exposure to the sun.
The walls of herb spiral store solar heat and pass it at night back to the plant. Gabion walls look very attractive and are suitable for spiral herb gardens, too. At the foot of the herb spiral you can even make a mini pond, which will retain the moisture in the lower area, or if you want, you can create a ?wetland where you can grow plants that love saturated soil.
Making a herb spiral is relatively cheap or almost free. It utilizes vertical space, which means you can grow more plants in small space. It also provides microclimates to different plants that mean you can grow more variety of plants. You can also make it on a concrete floor in your urban space.

How to Build a Herb Spiral

Build a herb spiral in a?spot that receives at least 5 hours of sunlight daily. A sunny spot is good, but if you live in tropics choose an area that receives shade in the afternoon. You can also make herb spiral on a rooftop garden or on a large balcony or terrace.

Materials Required for a Spiral herb Garden

? Limestone and?limestone rubble
? Soil
? Compost or aged manure
? Geotextile, pond liner or large container
? Gravel, crushed stones or wood chips for the driveway around the spiral
? Plants
? Working Tools: Spade, shovel, wheelbarrow, a stick, a rope and a measurement tape.

An 80-100 cm (0.8-1 m) high herb spiral should have a minimum diameter of 1.5-2 m.

How to Make a Herb Spiral

1. Decide where on the ground you?ll make a herb spiral. Plant a pole exactly at the center of that area and with the help of the measurement tape and rope, make a circle with a?stick and then mark it with limestone.
2.?Now erode the topsoil with the help of a shovel or spade to level the spot, also remove weeds and other debris.
3. If you want to create a pond or wetland at the foot of the spiral dig the soil more deeply at that point.
4. Before you lay the stones to make the wall, cover the excavation for the?future pond with pond liner and around the spiral and its path with geotextile to prevent the weeds. If you don?t want to use geotextile, lay the cardboards. You can skip this step?if you want.

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