The Micro Gardener blog shares how you can build a herb garden in 4 steps. Give yourself about 2 hours to complete this project. This is a super post with a lot of helpful information to help you build a herb spiral. What a beautiful way to dress up your outdoor space.
Want to make your own vertical herb spiral garden? This compact space saving design can be made with just a few basic steps.
Construction materials and methods vary so after deciding on the best position and gathering your materials, you can have one built the same day.
Depending on your budget and taste, herb spirals can be made very economically or be quite elaborate like this one with stone filled gabion walls.
Think of this as a typical ‘recipe’ you can follow, substituting ‘ingredients’ you have handy.
Gather edging materials e.g. bricks, pavers, stones, rocks – choose long-lasting materials for a permanent structure.
(Optional) pond materials and irrigation fittings if including.
Choose a spot that ideally receives 5 full hours sun/day and is close to your kitchen for easy access.
Orientate your pond or bottom of the spiral on the southern side in the Southern Hemisphere and northern side in the Northern Hemisphere. When it comes to planting, this will allow you to position your plants according to their sun, shade and water requirements.
Herb spiral with compass points.
STEP 1: Measuring up – Have someone hold or bang the stake into the central point of the ground where you want to position your herb spiral. To determine the perimeter, stretch out the string attached to the centre stake to mark out your circle, drawing a line in the soil with the other stake or bamboo cane tied on the end of it (or use chalk if you are marking out a hard surface).
An alternative method for marking out your spiral.
The diameter averages between 1.5 – 2m (5 – 6.5 ft) or 750cm – 1m (2.5 – 3.25 ft) from the centre.
Tip: If building straight on top of concrete, make sure you drill holes or have adequate drainage.
STEP 2: Your base – if starting on lawn you will need to stop weeds from growing. Cardboard can be used for this purpose to sheet mulch and build the spiral on top. No light = no weeds! Some people use newspapers or thick phone books instead but I choose to avoid adding anything to my organic garden with inks that may be based on genetically modified soy beans. Cardboard edges need to be well overlapped to block all light.
Cardboard is easily accessible for free from most businesses that pay to have it taken away and recycled + we can tread a little lighter on the planet at the same time!
Lay your weed mat or wet cardboard (soak with a hose or in a wheelbarrow) to cover the circle you have marked out. Cardboard will breakdown and add carbon to your soil and provides a food source for microorganisms. You may also choose to add some organic matter under this to accelerate breakdown of the cardboard such as chopped vegetable scraps and other green waste from your garden.
The base for this site has been pegged out, a gravel base laid and pond positioned.
STEP 3: Construct the wall structure – Using your edging material of choice, start laying your bricks/rocks on the outer edge and working inwards to create a spiral shape, allowing about 0.5m (1.6 ft) width to plant into or adjust if making a smaller spiral.
To minimise your cost and time, use the dry stone wall method where rocks or bricks are laid on top of each other, overlapping for stability.
For a more formal look, use mortar or cement between your bricks or stones.
Tip: Save your best looking materials for the outside ‘face’ and those that will not be seen on the inside of the spiral.
If using heavy rocks or stone, you may prefer to dig a shallow trench around the circumference of the circle and lay these into it on top of a layer of cardboard or weed mat to prevent weeds. If using the dry stone wall method, you may find it easier to add your organic materials as you go to provide support rather than adding these at the end for the mortar method.
Once you have your basic shape laid out around the circumference, add a second tier of bricks, remembering the outside ‘wall’ of your spiral is lowest (e.g. 2 bricks high or perhaps 1-2 rocks depending on size – enough to retain your soil).
Use more bricks or rocks to build the internal spiral walls, gradually increasing the height as you work your way into the centre.
The middle will usually end up about 1m (2.5 ft) high with a central planting area, gradually tapering down in height on a light slope to the bottom. You can block it off or add your bog/pond at the base if using.
To minimise the quantity of organic materials required, you may prefer to add some rubble to the centre where the depth is greatest before adding your organic matter.
STEP 4: Add your organic materials & nutrition – for each of us this will be different, depending on what you have easy access to. Some people only add mulch or straw to their herb spiral and plant into pockets of compost. If you’re on a tight budget or this is all you have access to, then this system of ‘growing soil’ will work fine but ‘dead dirt’ is unlikely to bring you a successful outcome!
“Like humans, plants thrive on good nutrition.”
Rather than buying in a trailer load of soil from your landscape yard, you can make your own soil teaming with living microorganisms. Soil that has a good structure (a crumbly fine texture that holds moisture well) is ideal for healthy productive plants.
These organic ingredients are likely much cheaper than buying in soil too!
Good sources of organic matter that will build soil fertility include:
Lucerne, sugarcane mulch and straw mulches all add organic matter to build soil.
Leaves from gutters are rich in nutrients & a free resource you can use to build your garden.
Sprinkle rock minerals (crusher dust from your landscapers is also suitable and very economical) and organic fertilisers as you add the organic matter to build in nutrients as a food source.
Soil Nutrition: Adding plant food that will release nutrients slowly while you build the spiral will reduce maintenance to a minimum.
If you have access to biodynamic preps you may choose to add these too. To assist breakdown and ensure there is enough moisture, water in each layer with liquid seaweed. Expect some natural settling to occur.
Tip: It’s a good idea to check the pH balance of your organic matter – it may be necessary to sweeten the soil with some dolomite lime if the pH is too high.
Moisture loving plants at the bottom of the spiral will thrive if you include some (optional) additional moisture holding ingredients like coconut fibre (coir peat), sphagnum moss, worm castings or some well aged compost (humus).
Diagramatic technical specifications plan – Full size printable.
Really cramped for space? You can still design a mini sized herb spiral!
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