Straw bale gardening is popular in permaculture. Maybe it’s something you would want to try in your own yard!
By Larry Hodgson
I’ve had a few questions about straw bale gardening over the years. I hesitated about writing on the subject, though, as I don’t really consider it to be a very laidback approach to gardening. However, there are ways of making it less time-consuming, so. . .
Yes, you can create a fast and easy vegetable garden out of simple bales of straw. And that means directly in straw, with the help of a bit of compost and topsoil. It’s really quite simple.
Oddly, the straw bale gardening technique comes to us from permaculture. You might wonder what such an ephemeral technique has to do with permanence (I certainly can’t figure that one out). However, such is the case. In some climates, the bales last only one year. Then you have to start afresh. I figure most gardeners can draw that out into a second year of culture. I mean, just because the bales themselves are slowly collapsing doesn’t mean you can’t grow plants in them!
Do make sure the bales you use are straw (residues of cereals after threshing, therefore without seeds) rather than hay (tall grass and other plants cut and dried as animal fodder, often including weed seeds).
You can buy bales of straw at a reasonable price from farmers or equestrian centers. Prefer 3-string bales over 2-string ones: they hold together better. Unless you own a van or trailer, also try to negotiate a price that includes delivery.
The Right Spot
Of course, the greatest thing about straw bale gardening is that you can do it anywhere that offers abundant sunlight . . . and a reliable source of water. (That last point is very important: this type of garden uses much more water than in-ground gardens!)
Straw bales can be placed on any flat surface: lawn (no need to remove the sod), patio, parking area, landscape fabric, etc. You could sell your car and turn your parking space into a bountiful vegetable garden! That would win you so many environmental Brownie points!
I wouldn’t recommend carrying straw bales up to an apartment balcony or rooftop, though. I’m sure neighbors would complain about bits of straw on the stairs and in the hallways! Plus, there will be soggy residues you’ll have to cart away at the end. So, accessibility is a factor.
You can simply set the bales on the ground. Just put down a few sheets of newspaper or cardboard first. For example, when you have a garden with really poor soil, you can simply drop a bale of straw on it and continue to garden. Likewise if your usual vegetable bed has a problem with soil-borne diseases that crop rotation can’t cure. Diseases won’t be able migrate into the straw, although the second year, when the bales have compressed downward, don’t allow any disease-sensitive plants to trail directly onto the contaminated soil.
Start by placing the bales. Lay them on their side, with the bale strings parallel to the soil and, if possible, the cut end up. This will allow more even water infiltration. Make sure you place the bales before you start to water. If not, they become heavy and almost impossible to move.
Install the bales about 2 weeks before the planting and seeding . . . and that will obviously vary according to your region. Somewhere in April to mid-May would be about right in many temperate regions.
You need to prepare the bales about 10 to 12 days before planting. This is done by covering the top with compost or manure or a nitrogen-rich organic fertilizer such as chicken manure or blood meal. Then water slowly, but abundantly: you really need to give that bale a good soaking!
You’ll be watering a lot at first. The bales have to be kept damp. And add more fertilizer every 2 days, as the microbes also need feeding.
Quite quickly, the bales will begin to heat up, reaching up to 60°C (140°F) if the straw is fresh, as the microorganisms, in the presence of this abundance of organic matter and nitrogen, develop and begin to digest the straw.
When the temperature drops to around 20°C (70°F), the straw will have decomposed enough to allow planting. Because of the heat given off by the decomposing straw, you can even install heat-loving vegetables (tomatoes, peppers, squash, eggplants [aubergines], tomatillos, etc.) a week or so earlier than usual, even if it means covering them with a floating row cover or blanket of some sort if nights start looking chilly.
Planting Your Straw Bale Garden
To transplant vegetables, dig holes in the straw and add some quality garden soil. Next, just set a young plant into each hole and cover its roots with soil. Space the plants a bit tighter than in the garden. Each bale would therefore offer enough space for, say 2 to 4 tomato or zucchini plants, 4 to 6 cucumber or pepper plants, etc.
You can also sow vegetables, the case with leafy greens, peas, beans, root vegetables, etc. To do so, cover the bale with a 5 to 8 cm (2 to 3 inch) layer of good garden soil (yes, directly on top of the straw) and sow as usual, using the spacing recommendations on the seed packet.
Which Vegetables Should You Grow?
Most annual vegetables can be grown in a straw bale vegetable garden.
Fruiting vegetables, especially, seem to like this technique a lot and give excellent yields. That’s because many of them like the extra heat this type of garden supplies early in the season. In fact, many straw bale gardeners specialize in fruiting vegetables like tomatoes, peppers, eggplants, beans, cucumbers, squash and melons
Leafy greens do very well in straw bales as well, as long as you don’t let them dry out too much. You can even sow them into the walls of the bale to gain more space.
Root vegetables—beets, potatoes, etc., and especially long radishes and long carrots—are not always as successful; the results are generally better the second year, when the straw has more completely decomposed. At any rate, to harvest potato tubers, you have little choice but to break the bale up. That ensures that the project ends after only one year.
Finally, find somewhere else to plant corn. It becomes too tall and heavy, so it tends to flop over, leaving its roots half exposed.
Obviously, it doesn’t make a lot of sense to grow perennial vegetables (lovage, rhubarb, asparagus, etc.) that take years to reach harvesting size in such an ephemeral garden. Stick to vegetables you harvest the first year!
Staking is a problem in straw bale gardens. Even when the stakes, trellises and tomato cages you insert into the bale seem perfectly solid at first, they’ll lean or fall over completely as the straw decomposes. You have to find some way to solidly plant them in the soil below . . . or fix them to whatever support is underneath your garden.
If your straw bale garden is set on soil, you can hammer tall T-bars into the soil at either end of the bale. Then run wires or twine between them for stem support.
Or just skip staking. You can do so by choosing less rampant vegetables, such as smaller determinate tomatoes, non-running squash, and dwarf beans and peas. Then all you have to do is to let them sprawl on the straw.
Straw bale gardening requires quite a bit of maintenance, but it’s mostly watering. You’ll need to water it often, daily in many cases, as the bales dry out very fast. A soaker hose would be very useful to take some of the pressure off. Or set up drip irrigation.
A surprising number of weeds tend to show up, but they sprout from seed (there’ll be no roots or rhizomes in straw!) and are therefore easy to remove. Just make sure to keep at it.
You do need a good source of inexpensive organic material (compost, manure, fertilizer, quality topsoil, etc.). After all, if you have to buy all the ingredients at full market value, the profitability of straw bale gardening drops considerably. Remember that you’ll have to replace the structure (the straw bales) every 2 years at least, because they collapse completely. Compare that with a raised bed or container garden. If you don’t have some sort of cost-free structure or container to start with, they require quite an investment at first. But afterwards you can make them last for decades.
One way of extending the life of your straw bale garden is to create a framework of wood, stone, brick or metal. One you can drop the bale into and that will help hold it together. That way, it will subside much more slowly. Also, you can fill in with soil or compost over a longer period of time as the mass continues to contract. By then, of course, it will no longer really be a straw bale garden. You might rather see it as an indirect way of creating a raised bed!
Well, at least when the bales have completely collapsed into a mass of organic matter, they’re still of great value. Just remove the twine and use resulting half-decomposed straw as compost or mulch elsewhere in your garden!