Straw Bale Gardening – A Beginner’s Guide

Whether you want to create new raised beds in your garden to save your back, or protect the soil, straw bale gardening is one of the interesting options to consider. Straw is an agricultural byproduct that is often readily available in agricultural areas. Hay bales can often be bought cheaply, and small numbers can sometimes even be sourced for free if you have a rapport with a local farmer.

What is Straw Bale Gardening

Straw bale gardening involves, as the name suggests, creating a garden from straw bales. In fact, the hay bales themselves become the growing medium – providing nutrients as they break down. Rather than growing food directly in the ground, or in raised beds filled with compost/ organic matter or another growing medium, in straw bale gardening, plants are placed in planting pockets of compost within the top of the bale. 

The Benefits of Straw Bale Gardening

Straw bale gardening has a range of benefits. For example:

  • Growing in straw bales, rather than direct in the ground, can be a great way to reduce your impact on the fragile soil ecosystem. It is one option for creating new growing areas in a no dig gardening system.
  • As the straw decomposes your plants will have plenty of food and it has even been said that plants could be up to 25% more productive when planted in straw bales than they would be if planted in average quality soil.
  • Due to the heat given off by the decomposition below, you can plant earlier in the year than you would be able to in the ground and can extend the growing season. 
  • If you use this method in a greenhouse or polytunnel/ hoop house, the decomposition will also generally serve to keep the temperature in your undercover growing area a little higher during the colder months.

Sourcing Materials for Straw Bale Gardening

A straw bale has a range of beneficial properties and can be an eco-friendly material to use in your garden.

Straw bales can be purchased cheaply direct from farmers. The Internet is a good place to start when it comes to sourcing straw bales near you, though if you live in the country there is no harm in simply asking at local farms to see if you can buy a few hay bales. This is an agricultural by-product and so often you can pick up a few bales of straw for next to nothing, and sometimes even for free.

Which Type of Straw To Use

The best types of straw to use for straw bale gardening are oats, rye or barley. Alfalfa and vetch straws may be easier to source, depending on where you live. Try to avoid using linseed or corn bales if you can, however, since the stalks of this kind of straw are coarser and therefore slower to degrade. Linseed (AKA flax) also contains an oil which slows down the process of decomposition.

Bed Edging (Optional)

In addition to needing the straw bale itself, you may also wish to create a raised bed structure around it, to keep it looking neater and tidier as the material breaks down. There are a number of different options that you could consider for the edging of your raised bed. 

For example, you might want to think about using natural materials that you already have in your garden such as:

  • stones or rock
  • logs, branches or woven fencing
  • clay/ mud or cob/ adobe
  • earth bags

You could also use reclaimed materials such as:

  • reclaimed bricks or blocks
  • reclaimed timber
  • an old bath or trough
  • household rubbish – ie glass bottles formed into a wall edging.

These are just a few examples of the sorts of edging materials that you could use for straw bale gardening. Remember, however, that you could simply place the bales in your garden and get going right away.

A Nitrogen-Rich Liquid Feed

In order to facilitate the breakdown of the straw bales for straw bale gardening, you will also need a nitrogen rich liquid feed which will start the composting process. Examples of nitrogen rich feeds which you could make include:

  • a nettle liquid feed
  • a grass clipping liquid feed
  • a liquid feed made from a range of weeds from your garden
  • a liquid feed made from the runoff from a wormery or other composting system

I use this old dustbin as a container in which to make liquid plant feed for my garden. 

A Small Amount of Compost

Finally, you will need a small amount of compost to create planting pockets in the top of the bale or bales. If you do not already do so, it is imperative that you start to make your own compost. This is something that you can do even in the very smallest of spaces. 

Creating a Straw Bale Garden

  • Choose a location for straw bale gardening.

Remember that if you are planning on growing annual fruits and vegetables in your straw bale garden, these will generally require plenty of sunlight. Choose as sunny a spot as possible. It is also a good idea to place it in a sheltered spot (or create a windbreak hedge or other screen to protect it from prevailing winds.

Think about whether the straw bale garden will be placed on hardstanding, lawn or, for example, on a patio, decking area or balcony. If the bale(s) is/are to be placed on a hard or man-made surface, it is best to raise it up to allow for good drainage. If you are building your straw bale garden on wooden decking, make sure there is a mechanism to remove excess water from beneath the bale, and separation between the bale and the deck, otherwise it can begin to rot. If you are starting your garden on grass or soil, it is a good idea to begin by laying a thick layer of cardboard beneath your bale. This will help to prevent weeds from growing up through it.

  • Source and position your bales, creating the bed edging around them if desired. The cost per bale will vary typically between $5 to $7 per bale. The number of plants you can grow per bale will also vary. As a beginner’s rule of thumb, stick to one plant per bale.
  • Condition the bales so they will start to decompose. ( This is achieved simply through ensuring that it stays wet for around a month.)
  • As your bale is conditioned, you could also be maturing some liquid feed. 

Liquid Feed

To make a liquid feed, simply add your chosen nitrogen rich material (grass clippings, nettles, blood meal or other weeds) to tightly fill around ½ a bucket and fill the rest of the bucket with water. Weight the materials down to keep them under water, and place a lid on the container since it really reeks. Leave the plant matter to break down over the month or so, then strain it to remove larger pieces of plant matter. Dilute the mix to a concentration of around 1 part of this liquid to 2 parts water. (Ideally rainwater that you have harvested on your property).

  • Add a good amount of this nitrogen rich liquid fertiliser to the saturated bale. This will activate and help to promote the composting process, and make nutrients available for your growing plants. Fertilize them every two weeks. 
  • After a month or so you will be able to detect through the bale temperature and its smell that this is working.
  • Now, create planting pockets of compost in the top of the bale where you wish to position your plants. (Be sure to think about the spacing requirements and nutrient needs of the plants that you have chosen to place in it.)
  • You can now plant up your straw bale garden. It is generally easier to use transplants sown in containers, rather than trying to direct sow seeds into your planting pockets.
    (Plants like squash and pumpkins will particularly enjoy the heat given off by the bale over the growing season, though many different plants will thrive in a raised bed created in this way.)

Maintaining a Straw Bale Garden

One important thing to remember about straw bale gardening is that it will require plenty of water, and will need to be watered frequently in dry weather. (It will tend to dry out more quickly than a raised bed filled with soil/compost. 

Installing a drip feed irrigation system could be a good idea. This could be linked to a rainwater harvesting system on your home. For smaller systems, you could also consider making or buying some drip feeding watering globes or plastic bottles, with holes pricked into the lids, filled with water and placed upside down in the soil.

The bales will only last for a few years, as they will decompose over time. But by the time they break apart more completely, you will find you are left not with a mess but with a high quality compost which you can still plant into at a lower height, or remove and use elsewhere in your garden. 

If you created edging for your straw bale garden, you can refill the structure and recreate the initial height by continuing to add organic matter to the top of the bed through sheet mulching with straw, green organic matter and compost. Alternatively, you can clear out the decomposed/ decomposing straw to use elsewhere in your garden and place another straw bale to refresh the growing area. 

If straw is readily available where you live, a straw bale garden could be a great idea. So why not consider making one in your garden?