The Charleston Gardener: Straw bale gardening

By Louisa Cameron

Quite a few years ago, I had to come up with part of a program for my garden club. The other half of the program was on vermiculture, or keeping a worm farm for composting and harvesting the nutritive castings. We have about 28 members of an enthusiastic group in our club and we enjoy a wide variety of topics. I had read about straw bale gardening for vegetables and thought it would be fun to give it a try.

This type of vegetable gardening is fun — but it is not for everyone. It takes patience, for the preparation and gets messy, although some enterprising gardeners will contain the bales in several different ways, including chicken wire and boxes made from pallets.

Getting started

I researched everything from books to Facebook pages on the subject of straw bale gardening. Ideal resources are Straw Bale Gardens by Joel Karsten and LayLa Burgess’s article “Straw Bale Gardening” on Clemson Cooperative Extension’s Home and Garden Information Center website; she graciously provided the photos for this article.

For ease of introduction, here are my condensed notes:

Straw bales are readily available at farm supply stores. Red Top on Highway 17 South just past the Main Road intersection usually has them in stock, but I would call first (843-763-6651). The cost is about $5 a bale. I can only fit four bales in my SUV — they are much larger than pine straw. Be certain you get straw and not hay, or you’ll have grass popping up all over.

Be sure you know where you want to place your bale(s). They are too heavy to move when wet! Unless you are growing lettuces and other greens that do not need full sun, you must find a spot that receives at least six hours of full sun every day. Vegetables tend to get mildew, have more pests and will not be very productive otherwise.

Place bales cut side up! Straw is hollow, unlike hay, which is not suitable for this type of gardening and has seeds that will spring up everywhere. I once used hay for mulch that was not well-rotted and had to pull up blades all over the flowerbeds and the lawn. Several gardeners recommend placing cardboard under the bales.

You may want to place a soaker hose and pins right away on your bale(s) to cut down on constant watering and to water the plants from the bottom, which is ideal.

Plan a large straw bale garden carefully, with landscape fabric, wood chips or another type of mulch between rows to prevent weeds. You might want to grow vertically and will need a wire trellis structure; it should last quite a few years. There are good instructions in books and on the internet for making these and they can be quite attractive.

Conditioning the bales

Condition the bales as follows with basic fertilizer, preferably one with a high nitrogen content. Lawn fertilizer is fine and usually has a ratio of 10-0-2. In order, the elements in this ratio are nitrogen, phosphorus and potassium. There are often minor elements added as well.

Per bale:

Day 1, sprinkle on 1/2 cup granular fertilizer and water in well.
Day 2, soak the bale thoroughly with water.
Day 3, use 1/2 cup fertilizer watered in well.
Day 4, water thoroughly.
Day 5, 1/2 cup fertilizer watered in well.
Day 6, water again.
Days 7, 8 and 9, use 1/4 cup fertilizer watered in well.
Day 10, use 1 cup balanced fertilizer (I use 10-10-10) and water it in very well

By days 12-18 you should be ready to plant and will have to guess a bit about the timing, as warmer weather makes a difference. You should have a “cooking” bale and should see little black specks throughout that represent the beginning of the straw breaking down into soil. The temperature of the bales should be up to around 85 degrees.

It is extremely important to devote yourself to conditioning the bales for the full 12-18 days and probably the longer, the better.

Adding plants or seeds

For transplants, dig right in with your trowel. You may have to remove a little straw. The soil from the transplant pot is usually plenty for the plant.

For seeds such as lettuce, spread sterile planting mix in a one-to-two-inch flat layer on the top of the bale and plant according to directions. You can also use store-bought or homemade seed tape. To make a seed tape, mix equal parts of flour and water to use as a paste on paper towels. Graph paper underneath or a ruler can help you space seeds according to the directions on the packet. Using a small craft brush, dab on blobs of the flour paste and place seeds. Cover with another layer of paper towels, press together and let dry in a cool spot. Label, roll up and use at planting time, layering on top of potting soil and covering with the soil to the correct depth. You can cut the paper towels into strips.

Joel Karsten, who wrote Straw Bale Gardens, reports that “What remains after your harvest is gold.” His book is available from Amazon.com for around $20 and contains planting suggestions, vegetable charts and instructions for compost bins, trellises, etc. The website is www.strawbalegardens.com and there is also a Facebook page.

Final comments

Using straw bales was not a successful method of planting in our formal garden, but I would not hesitate to try it again if I could find a spot that got more than six hours of sun a day and was not on display. Our garden is completely surrounded by crape myrtles and is in the middle of the city, with houses and walls at our boundaries along with the trees. I may put one bale in a hot spot and grow tomatoes in it. It would be fun to attempt it again, and my compost heap would benefit from the used bale the next season. I could even put a bale next to the compost pile for convenience.

Finally, there are hundreds of visuals on the internet, including YouTube and Pinterest, to help you with this type of gardening. Clemson’s Cooperative Extension website has clear, excellent instructions with illustrations. It’s a particularly good project for children, although it takes patience for the first few weeks and it’s a great way to use up those leftover Halloween straw bales next spring! The miniature bales available for decorating can be used as a fun experiment in straw bale gardening if you are not sure about plunging in with big bales, and splitting a bale with a friend, neighbor or relative is another option. The main point is to enjoy trying something new in the wonderful world of gardening.

Louisa Huger Pringle Cameron is a native Charlestonian married to Price Cameron, a retired plastic surgeon. She is the author of three books on the gardens of Charleston, enjoys duplicate bridge and is a proud grandmother of three.