Straw Bale Garden vs Traditional In-ground Garden – A Critical Comparison

Robert Pavlis

Straw bale gardening seems to be an “in-thing” to try and I have written about it in Pros and Cons of Straw Bale Gardening. I see people on line praising the technique, but I also see a lot of people reporting failure. What is rare is any side-by-side comparison of straw bale gardening to traditional in-ground gardening. Even proponents of straw bale gardening don’t provide evidence for their claims by making a comparison.

I wanted to see for myself how well it worked, so this year I decided to do a comparison between my traditional vegetable garden and straw bale gardening. Here is what I found.

Straw Bale Garden vs Traditional In-ground Garden
Straw bale garden vs traditional In-ground garden

Straw Bale vs Traditional Gardening – Experimental Setup

I set up two straw bales and planted the same things, at the same time, in each one, as well as directly in soil in my normal zone 5 garden.

After conditioning, the Control Bale was treated just like my soil garden. It was fertilized and watered whenever I did the same to my soil garden. I wanted to treat this bale as closely as possible to my normal garden practices to do a proper comparison of the two techniques.

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The Test Bale was also conditioned but after that it was treated according to the suggestions made by happy straw bale gardeners it was watered whenever it started to dry out (which was daily on hot days) and it was fertilized every week.

Both straw bales were conditioned as described in my previous post. All three gardens are within a few feet of each other so they all get the same amount of light and air temperature.

The Straw Bale Conditioning Stage

Traditional Garden

I raked last years straw mulch off in early April to allow the soil to warm up. That’s it. Nothing else was done.

Straw Bales

Conditioning started April 5, which is about 2 weeks before I normally plant cool weather crops. Early April this year was unusually warm with daytime temperatures in the low teens (centigrade).

Conditioning ended April 14. April 13 to April 17 was very cold with daytime highs of 3-5 C (37-42 F).

I followed the advice to water daily, but this did not seem to make much sense to me. Once the bales were wet, they never dried out and probably only needed to be watered every 3 days. All this extra water probably washed a lot of the fertilizer right out the bottom of the bales.

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There was no visible decomposition during conditioning and the bales never got warm to the touch, even in the center of the bales. I suspect that conditioning has to wait until warm weather, but this is never mentioned in the procedures for this technique.

By June 28, the straw was turning darker, showing some signs of decomposition. Conditioning took about 10 weeks, not the 2 weeks claimed by many.

Planting Cool Weather Crops

Sugar Snap peas were planted in the ground early April but none were planted in the straw bales because they were still being conditioned. This is a major drawback for straw bales. The peas in soil were an inch tall by the time the bales were conditioned and ready for planting.

The first planting in straw took place on April 22. An inch or two of soil was placed on top of both straw bales. Both bales and my normal ground were planted with a row each of carrots, beets and lettuce. A few radish seeds were also added to the beet row.

Germination of Early Planting

The first half of May turned out to be quite cold and by May 9 we had nights of -4 C (25 F).

Lettuce was poking out of the ground by May 1 and by May 7 beets and radish were also showing in the ground.

spring crops grown in soil
spring crops grown in soil

Nothing germinated in either straw bale.

I suspect that the straw bales were colder than the ground which slows down germination. The other problem is that watering the bales washed the soil down the sides of the bale and into the bail. A week after sowing, I could see radish seeds siting on the straw which would make it hard for them to get their initial root into the bale without drying out.

Soil on the straw bales also dried out much quicker than the ground. Everything was watered daily, either from the tap or by rain, but it might not have been enough water for the bales. The soil on the bales dried out very quickly and much faster than the ground.

Carrots, beets and lettuce were harvested normally from the ground but these crops were a complete fail on the straw bales.

Late Planting of Peas in Straw Bales

I had germinated some sugar snap peas in pots for another experiment and these were about an inch tall, so I decided to plant one in each location on May 8. The peas were in 1/2 gal pots which were easy to plant in the ground.

Planting in the bales was more difficult. Since the straw still had not decomposed, it was hard to dig out enough straw for all the soil in the pot. So I removed half the soil from the seedlings and planted them in the straw.

The pea plant in the control bale started to grow a bit, and then died. I think its root system never get established.

The test bale did much better. Growth was as good as in the ground, and the first flowers showed at the same time as the plant in the ground. Unfortunately, chipmunks cut off the stem a few days before harvest time, so the peas never fully developed. However, I am sure the production would have matched that of the same pea plant in the ground.

For comparison, the early planted peas that were planted in the ground were 5 feet tall by harvest time. At the same time, this late planting was only 2 feet tall in both soil and in the bale,  and were not ready for harvest. The early planted peas also produced more pods. Early planting of peas in cold climates is very important.

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Growing Beans in Straw Bales

Beans grown in soil
Beans grown in soil

Blue Lake pole bean seed was planted early June in both bales (2 seeds per bale) and in the ground. Only one of the seeds sprouted in the test bale, while both sprouted in the control bale. The ones in the ground showed normal green coloration. The one in the test bale was a bit darker, due to the higher fertilizer rate. The ones in the control bale were very light green, almost yellow, probably due to a nitrogen deficiency.

June 30:

Ground – the beans were already climbing and were 2-3 feet tall.

Control bale – no sign of climbing and plants were only 6 inches tall.

Test bale – same as the control bale

July 13:

bean grown in control straw bale
bean grown in control straw bale

Ground – beans were 4-8 feet tall.

Control bale – plants are 2 feet tall and leaves are still fairly yellow.

Test bale – plant is 8″ tall, still not showing signs of climbing, but it is darker green.

August 1:

Ground – harvested first beans and there are lots of small beans and flowers.

Control bale – flower buds showing but none open yet. They are at least 10 days behind beans growing in the ground with first flowers finally opening August 9.

Test bale – same as control bale.

Bean grown in test straw bale
Bean grown in test straw bale

Bean seed did grow in the straw bales, probably because the seed is larger and the straw was starting to decompose by the time they were planted. Growth was slower in both bales and harvesting started about 10 days after the peas in the ground. In a short season like you have in zone 5 – a 10 day delay is significant.

Growing Tomatoes in Straw Bales

Late May and early June were colder than normal, so tomato planting did not take place until mid June. The cultivar Early Girl was planted in the ground, and one plant was added to each straw bale. The straw was starting to show some decay, but not very much. The plants for the straw bale were planted in a hole about 4″ deep, along with soil from the pot. The ones put in the ground were planted with about a foot of stem covered in a shallow trench, as is my normal custom.

This deep planting is expected to provide larger plants with larger root systems but it is not a suitable method for planting in straw bales because you can’t dig a deep enough hole.

Tomatoes grown in straw bales; left on is the control bale, the right one is the test bale
Tomatoes grown in straw bales; left one is the control bale, the right one is the test bale

June 30:

Ground – plants were 18 inches tall and are starting to flower.

Control bale – plant has made limited growth of a few inches. It was showing flowers but the leaves were yellow-green.

Test bale – plant was growing well, had flowers and dark green leaves. These leaves were even darker than the plants in the ground.

July 13:

Blossom End Rot (BER)
Blossom End Rot (BER)

Ground – none of the tomatoes showed blossom end rot (BER) and I rarely see this in my garden.

Control bale – tomatoes are a bit smaller than in the other two locations and they show no sign of BER.

Test bale – the largest tomatoes are showing BER and were removed. BER is due to a lack of calcium in the fruit which is usually caused by watering issues.

Note: The BER was only a problem on the first few tomatoes of the season and only in the test bale. Later fruit was BER free in all three situations.

Aug 5:

Ground – harvested the first ripe tomato.

Both bales – plants are growing well, producing a good quantity of tomatoes, but none are ripe yet. Plants seem to be about a week behind the ones in the ground.

Because tomatoes are planted later in the season there is enough time in spring to condition the bales before planting. Growth in the bales was surprisingly good, although not better than growing in the ground and the harvest started later.

Straw Bale Gardening vs Traditional Gardening

A big issue with straw bale gardening is the extra effort needed to make this method work. You have to get the bales and then go through the conditioning process before you can plant. It is clear from the above, that the conditioning process does not work in a cold climate for early crops. It might be possible to condition the bales during the previous summer so they are ready for spring planting, but that is not normally advocated. In comparison, the soil is ready to go anytime.

Straw bale gardening requires more water and fertilizer than traditional gardening. Water is becoming a scare resource in some areas, and all that excess fertilizer will end up in local rivers and lakes causing unnecessary pollution. Not to mention the extra cost.

Once my seeds have sprouted in soil, I only need to water once or twice a week if we get no rain. Why would I want to water every day?

Crops seeded in early spring, in my climate, don’t work in straw bale gardening. They might have a chance if the bales are conditioned the previous summer, and they probably work in warm climates.

Transplants which are planted later in the season, like tomatoes, do work in straw bales but even for these the total harvest period is shortened; a problem for short season climates.

What does the straw add to the process? There is some decomposition, but the amount of nutrients this would add during the growing season is minimal. The material provides a lot of air to the roots, but also requires much more watering to prevent drying out. The bale is higher, so it does mimic a raised bed. The plants are basically growing in the water surrounding the pieces of straw, very much like a hydroponic system.

Conclusions:

  1. There seem to be no benefits in using straw bales over conventional growing in the ground.
  2. Traditional gardening is less work, allows for an earlier start to the season and requires less fertilizer.
  3. None of the crops tested performed better in straw bales.
  4. You can’t treat the straw bales like you do your traditional garden. Doing so results in plants that are stunted because they don’t get enough water or fertilizer.
  5. Straw bale gardening is just a complicated way to do hydroponic gardening.

Should you use straw bale gardening? I think that it has a place where there is no soil, or the soil is too contaminated for growing food. Other than that, traditional gardening is a better option.

If you use it in zone 6 or colder, you should condition it the previous summer. That means that you need space for two bale gardens – one for this year with plants, and one for next year. Seems like a waste of space to me. Colder climates that don’t have any soil may be better off going with containers.

Does straw bale gardening work? Sure it does, and I am sure that with more experience my crops would do better, but even if that happens it is still more work and wastes resources. Growing in soil is so much easier.

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Robert Pavlis

I have been gardening my whole life and have a science background. Besides writing and speaking about gardening, I own and operate a 6 acre private garden called Aspen Grove Gardens which now has over 3,000 perennials, grasses, shrubs and trees. Yes--I am a plantaholic!

13 thoughts on “Straw Bale Garden vs Traditional In-ground Garden – A Critical Comparison”

  1. I’m also in USDA zone 5, and we have heavy clay & gravel soil. Reading this article, I’m inspired to try straw bale for growing burdock roots! They grow effortlessly, but are almost impossible to harvest in one piece. Being able to simply pull the bale apart might be the solution!

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  2. I too experimented with the straw bale (barley straw) idea here in the Pacific Northwest Skagit County near the water zone 8b. It was a lot of work and I should have lugged a few bales out there in February to get a jump on the conditioning. I live on a farm and my garden is on a spot that’s been gardened for more than 50 years- likely more like 100. Tons of earth worms! Periodically it gets limed (our native soils tend to run acidic here) chicken and cow manure to over winter. I just found the straw bales to be extra work and all they were in the end was compost that got tilled in. Now I take my household compostables- coffee grounds and filters and any egg shells and vegetable/fruit materials and just bury them randomly all season long in the garden and flower beds. In a couple weeks there is not even any filter material left- all gone. I might find bits of egg shell that soon but it mostly is all consumed by the bugs in the soil in relatively short order. Washington State University also did the cotton panty test and although I never squandered a pair of my own, I’m confident given the extremely fast response of the household compost getting eaten that it’s pretty lively. Thank you for your videos, they largely confirmed the knowledge that has been passed down and our own experience as farmers!

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  3. I had good success with straw bale gardens, but they were an adaptation to make school gardens at schools with black top surrounded by tall chain-link fence without available green space. For a “test ” I planted 3 six-packs of seedlings, three of each pack in the straw bales, the other 3 in a soil garden. Two of the soil garden seedlings fell to bunnies, but all of the others grew faster and were more productive than the ones in straw bales. So garden soil is better. However, the straw bales provided garden space for schools without having to launch a huge initiative to remove black top or safety concerns of allowing students to leave the fenced ares, or concerns about contaminated soil and without the effort required to bring change to an institution. All we needed was the go-ahead of our principal and with could make a garden. Vines grown in the straw bales provided a little shade, much needed on back top, and some kids tried tasting the veggies that they had planted.

    So, while straw bales may not be superior to lots of green garden space; they are a great low cost unban alternative, provided you can get bales that are free of persistent broadleaf herbicides.

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  4. Excellent post and good work doing the side-by-side. Another issue I have written about with straw bales is the high chance of contamination with long-term persistent herbicides such as aminopyralids. At this point I am convinced that straw bale gardening is more of a passing fad than a good gardening method. The rewards seem minimal.

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  5. Informative article, Robert! Aahh… My very first garden was straw bales, as directed by Joel Karsten. It was an exhausting failure… From my experience, among other common problems, the pests were terrible, especially slugs and earwigs. When I finally dismantled the garden(after only one season), the bales were polluted with slugs! Anyway, that failure spurred me to become critical, researching other methods. No-dig gardening has been good to me. Standard container gardening has worked well, too. In my opinion, Karsten is just a typical salesmen, promoting his book with no mention of gardening sciences. He has made a lot of money with this novelty by selling his book to unsuspecting gardeners… Something else to consider: the presence of herbicides in cereal straw(oats, wheat, barley,etc.) is very, very likely.

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  6. I use alfalfa hay bales as opposed to straw. There are no beneficial nutrients in the straw whereas the alfalfa contains nitrogen as well as other nutrients. The bales have to decompose to incorporate into useful organic matter. My ground soil is hard clay that certainly needs organic matter to make it more arable. This was my second season of doing this and this year I added 4”+/- of garden box soil containing manure. My results to last year were similar. I probably watered too frequently, but I wanted greater decomposition of the bales. Next spring I plan to turn over the whole bed and add 6”+/- more of the box mix on top. I have a raised bed up about 15” from ground soil level. This is a new method of gardening I have never tried, but I am in NW Colorado at about 6400 ft. elevation. I have certainly enjoyed the past 2 seasons and look forward to as many more as God grants me. Enjoyed your post.

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  7. Disease…. lots of disease in my soil, none in a straw bale, conditioned with clean nutrients, tomatoes plants thrive without septoria leaf spot, etc.

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  8. I get my straw bales from people who use them for fall house decorations and leave them out of doors all winter. By spring they have already started to decompose and they do not need to be conditioned. This means that I can plant them at the same time I plant my regular beds. I also only plant light weight crops in mine, lettuce, green beans, Swiss chard and similar crops. I tried Brussels sprouts one year and they fell out of the bales around harvest time because the straw and broken down so much. I find the bale gardening useful because I have a very tiny yard and it allows me to grow a crop on my driveway without having to buy an earth box or other temporary container

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  9. My daughter is using straw bale gardening to get organic matter into what was a very sandy back yard. This spring she buried her straw bales and planted her tomatoes in them as a way to form a water sponge and increase water retention in the early season until the tomatoes got their deep roots established. The result was that she watered the tomatoes every other week or so, completely drenching the bale trench. She didn’t hardly water them during the drought at all and they were perfectly happy.

    Her potatoes successfully reached and maintained a very warm soil temperature allowing her to plant in March in eastern Ontario, tenting them with plastic was essential for this. But she wasn’t planting in the straw bales, she was using them as walls to keep the soil in. So she calls this “straw bale augmented” gardening.

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  10. I successfully incorporate bales as part of my ongoing soil improvement process.
    In Mesa, AZ we face several challenges:
    Alkaline humus free clay
    Flood irrigation every 2 weeks in the summer
    Temperatures in full sun that can be as high as 144 dgrees measured with a lazer thermometer.
    I use 8x8x16 block two high to make raised beds and truck loads of horse and chicken compost to improve the soil.
    Flood irrigation is a problem for unteathered bales – they float away, and when saturated are almost impossible to relocate.
    I have two beds dedicated to tomatoes and they get new bales each year. The bales are planted 6 inches apart, parallel, and long side down. Once conditioned they are covered with compost and the gaps between filled with compost. The gaps are where the tomato 1 gal pots go. Nicely seperated and needing minimal extra fertilizer. I get wondefurl crops of tomatoes and peas.
    I too have found that few other veggies do any better in bales.

    First note: Do not cover and fill gaps until conditioning has finished. One year I made the mistake of filling too early and the bales never came down from 140 until the flood irrigation came through and cooled them off.
    Composted chicken manure makes a great growing medium on top of the bales.
    Overall the cost of the bales is a problem, but they are cheaper than buying dirt for the beds and the bed’s soil is progressivly improving each year, with the addition of the old composted bales.
    The raised beds are very productive with over 40 different varieties of vegies.

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  11. Summer of 2019, I experimented. Plastic tubs with drainage holes, set on the ground. 6″ of Miracle Gro Potting mix, layered with about 4″: of straw. I kept alternating the layers until the top of the approx. 22-24″ tall tubs. Tubs are 22″ wide. Planted certified seed potatoes at the proper depth.
    Harvest time, NOT EVEN ONE potato had formed in the straw!! Potatoes in the potting mix grew as usual. Certainly not a scientific method but enough to tell me that straw bale growing was not for me.

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  12. Thank you for taking time to do this. Your experience is what I’ve imagined about this method. It makes me wonder: Is there no better way to cultivate food crops that the most natural, ancient way, in soil with the best conditions we can provide. But since gardening is a pleasure too, it’s fun to try out other methods and see what happens. What YOU do for us is to prevent these other methods from becoming the only, best, righteous way to garden. You do this by simple scientific method: observation, procedure, recording results, drawing conclusions based only on results. All the old OLD gardeners I’ve know have used this same method, instinctively. There was no “magic” in their methods, but there was much pleasure in their gardening.

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