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
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.) We outlined how to do this below.
- As your bale is conditioned, you could also be maturing some liquid feed.
Conditioning the Straw Bales
To turn your plain straw bales into a good habitat for your vegetables to thrive, you’ll have to condition every bale to turn it into a growing medium. This is the most time-consuming part of the whole project, but nature will take care of most of the work for you. You’ll have to:
- Days 1 to 3: Once you pick out a place for the straw bales, you’ll have to get out your garden hose and water everyone thoroughly. Soak each bale and do this once every day for three days. This will kickstart the conditioning process because the bales start to decompose. As the microorganisms start working, it can increase the temperature inside of the bale.
- Days 4 to 6: When days four to six roll around, you’ll need to sprinkle fertilizer on top of the bales. Every bale should get one cup of 21-0-0 ammonia sulfate or a half cup of 46-0-0 urea. The numbers refer to the amount of nitrogen, phosphorus, and potash in the fertilizer. These are industry-standard measurements. These all have higher nitrogen contents because this is what will speed up your conditioning and decomposition. You should water it thoroughly after you apply the fertilizer.
- Days 7 to 9: You’ll keep fertilizing once a day on days seven to nine, but you want to cut whatever you’re using half. Keep watering thoroughly after each application.
- Day 10: When day 10 comes around, you can now stop adding fertilizer. You should keep watering to keep the hay bales moist.
On day 11, check your bales. If the bales feel around the same temperature as your hand, you can now plant your vegetables. If it feels hot to the touch, you want to water them really well and check it again the next day. The goal is to get bales that feel warm to the touch but not hot.
Spring Straw Bale Garden by Scott Sherrill-Mix / CC BY-NC 2.0 If you don’t condition your straw bales, your vegetables won’t do nearly as well because they won’t begin the decomposition process until later in the growing season, and this can deprive your plants of nutrients.
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.)
Planting Vegetables in Straw Bales
When you finish conditioning your bale, it’s time to pick out which vegetables you want and plant them. You can plant every bale with the following:
- Cucumbers: Four to six plants per bale
- Peppers: Four plants per bale
- Squash: Two to four plants per bale
- Strawberries: Three to four plants per bale
- Tomatoes: Two to three plants per bale
- Zucchini: Two to three plants per bale
It’s also possible to grow green beans and lettuce in your straw bales, but the number of plants you have per bale will depend on the variety you plant. Check on the seed package. Beans and lettuce will grow very easily and quickly by directly sowing them into the bale.
Get a trowel and use it to dig on top of the straw bale. The hole should end up being around the size of the container your vegetable plant was originally in. Slide the plant out of the container gently. If it should stick, you can tap the back and sides of the container to loosen it up. Don’t try to tug it out by the stem because you can easily break or damage it.
Put the plant root-side down into the hole. Gently pile your straw back into place around the soil and onto the roots. Water your plants well.
A row of straw bale tomatoes in my garden by Laura Hamilton / CC BY-NC-ND 2.0 Picking out the correct plants to put in your straw bale garden increases your chances of getting a higher yield each season.
What Not to Plant in Straw Bale Gardens
Not every vegetable you can imagine will grow well in a straw bale garden. Some won’t do nearly as well as other picks, including:
- Corn is usually too top-heavy and tall to grow in this type of garden
- Sweet potatoes, potatoes, turnips, carrots, and other root crops won’t survive well here
For the average gardener, managing to grow a few peppers and tomatoes is reward enough. They’re a lot more flavorful when you grow them using this method than they would be if you bought them from the store.
Special Considerations: Tomatoes and Vine Crops
Tomatoes and other vine crops like squash, cucumbers, and zucchini will need more support if you want to plant them in your straw bale garden. You should stake your tomatoes as they grow upward to give them plenty of air circulation around the leaves. A traditional tomato cage won’t work well in your straw bale garden. Instead, you’ll have to drive stakes into the ground using a hammer or mallet. They should go all of the way into the ground.
Once you finish, you can cut up some old sheets from your bed into strips and use them to tie the stake to the plant. Don’t use metal stakes because they can heat up inside the bale and scorch or burn the plants. Fabric ties are much better than plastic twist ties because they’re more forgiving on the stems.
If you want to grow beans or cucumbers, choose bush over pole varieties. Bush beans and cucumbers grow in a shrub-like plant with a low profile, and you don’t have to stake them. If you have seeds for pole beans handy, you can still grow them in the straw bale. However, you’ll have to stake them like you did the tomatoes so they have support.
Squash, cucumbers, and zucchini can spread downwards, out, and slowly move away from the straw bales. This can be a problem if you try to cut the grass between the bales. You might want to offer more support so they grow upwards insead.
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?
Straw Bale Gardening Tips
You’ll need to keep the bales well-watered, and they can dry out quickly. The straw should hold up for a full growing season. They’re generally held together using one or two strands of metal baling twine or rope, and this helps them retain their familiar shape. You should water the garden every day and skip it when it rains. Straw also has no nutrients of its own, so you need to feed the plants frequently. Ideally, you’ll fertilize them once every two weeks while your plants are starting out, and increase it to once a week when they start bearing fruit.
- Use Straw Instead of Hay – Hay comes made from grasses and alfalfa that still has seeds attached. The seeds will eventually turn into weds and germinate before sprouting. On the other hand, straw has leftover stalks of grains like wheat and oat in the composition. The seeds have already been removed through the harvesting process. So, straw is almost weed-free, and this makes it much easier to take care of.
- Put it Near a Water Source – If it’s possible, you want to put your straw bale garden close to a source of water. Any garden uses a decent amount of water, and you want yours to be within easy reach of the hose.
- Consider Solarizing – If you solarize your bales by wrapping them in black plastic a few weeks before you plant them, the heat will build up and kill any seeds that could sprout later. It also speeds the decomposition process up and the plants can use these nutrients. Before you begin planting, strip the plastic away.
- Grow Short Plants – Sunflowers, corn, tomatoes, and other taller, upright plants can grow too large to have adequate support by the bales. Stakes are also challenging to use unless you can drive them down into the earth through the bales. You can grow smaller varieties of these tall plants, or you can prune them.
- Full Sun – Almost all vegetables and herbs like full sun. They should get between six and eight hours of sunlight a day or more. If you have one of these gardens in partial shade, make sure you adjust what you grow and plant leafy vegetables and lettuces.
- No Pooling Water – Don’t put your straw bale garden in an area that is low-lying because it’ll encourage water to pool. Too much standing water can easily trigger rot in the bales or drown the plants.
Straw Bale Garden Problems
Most of these gardens have a few problems, and this is why they’re so popular. The most frequently reported issue is dry bales. Again, you want to keep watering to avoid, especially during the hot summer months. Mushrooms are another problem with these gardens. However, they’re also a sign that they’re working like they should be because they’re slowly decomposing.
If the sight of mushrooms in your straw bale bother you, it’s possible to pick them off by hand and throw them out. You should never eat any mushrooms that grow in this garden because some can be poisonous. Leave them alone unless you’re an expert and identify them.
- Because the bales are permeable and above ground, they’re prone to drying out quickly. Make a point to water regularly. A soaker hose or a drip irrigation system work well.
- You can use mushrooms to get rid of any unwanted seedlings. The mushrooms should disappear by themselves.
- Regular feeding is important because watering the bales frequently will lead to quick nutrient loss. Feed them once a week during the active growing season using a balanced plant food that is water-soluble.
- Because the vegetables don’t sit right in the ground, it can be a pest deterrent. Slugs can be a problem if you plant bush beans, but sprinkling a small amount of diatomaceous earth can help.
- By season’s end, the bales will break down. How much they break down depends on the weather and what you grew in them. Some will hold up enough to plant garlic and others will collapse into a rich compost.
Frequently Asked Questions
1. What types of plants will do best in this garden?
There are several types of plants that will do very well in this garden as long as you take care of it correctly. They include annual flowers, annual herbs, Asian vegetables, beans, eggplant, garlic, kale, peppers, potatoes, squash, strawberries, and tomatoes.
2. When is the best time to start a straw bale garden?
It is possible for you to start this type of garden in the early fall months. However, you should wait until spring to plant the vegetables.
3. How much does a bale of straw cost?
Your straw bales can cost anywhere from nothing to over $10.00 each. In some locations, local farms might give them away free if they have extra taking up space in their barn. Other people might charge a small fee per bale.
4. Can you use straw or hay in the garden?
You can use hay in the garden, but you’re also opening the door for tenacious perennial weeds to dig in like thistle due to the seeds laying dormant in the bale. On the other hand, straw works wonderfully for garden mulch because there are no sneaky seeds inside it.
Using this quick guide, you can create a straw bale garden that will thrive all season long, and you may even be able to sneak in an extra crop in the later fall months. Concentrate on growing lower profile vegetables for the best yield potential, and water it thoroughly.
Elizabeth Waddington is a smallholder, permaculture designer and environmental consultant. When not designing food producing systems or advising growers around the world, she is to be found in her own garden. On her 1/3 of an acre patch of land she has a walled forest garden orchard (home to rescue chickens), a polyculture vegetable plot, a polytunnel, wildlife pond, wild woodland garden and more and is working every day towards greater self-sufficiency. She is passionate about sustainability and loves to inspire others about the wonderful things home gardeners can do for people and planet.