Thursday, May 12, 2011

Straw Bale Gardening

Last night I went to a Straw Bale Gardening demonstration conducted by Cathy Egerer. I was looking for a solution to the short growing season here in Grand Marais. For the last two years I did not get very many ripe tomatoes. I've decided to include information from the demonstration in today's posting for those of you who want to garden, but want it to be a bit easier.

Straw bale gardening isn't a new idea. However, it is gaining in popularity because of its simplicity as well as its flexibility. This method of gardening involves planting directly into a straw bale (not hay, which has too many seeds. The straw serves as the planting medium, rather than soil. Since the bale heats up as it decomposes it keeps the plants warmer than they would be if planted in garden soil. Best of all, a straw bale garden can be planted anywhere the bales will get at least six hours of sun -- even on a concrete or gravel surface.

What You Will Need--The number of straw bales you wish to plant.
--Approximately 3 1/2 cups of high-nitrogen granular fertilizer per bale (at least 20% nitrogen -- which is the first number in the fertilizer's formula). Do not use anything with weed killer in it.
--Stakes if you plant tomatoes or taller vegetables.
--Approximately 1 cup of 10-10-10 (or similar) basic granular fertilizer per bale.
--Bag of potting soil.

Placing Your BalesChoose a sunny spot to set the straw bales. Once the bales are saturated, they will weigh over 400 pounds each. So make sure the bales are placed where they do not have to be moved. The spot should allow water drainage underneath since excess water will drain right through the bales. If you are planting more than one bale, you can place them end-to-end in a row or side-by-side to make a square. If planting rows, try to leave 24 inches of space between the rows to allow access for harvesting the vegetables. If your bales get sun in the morning, it will help dry the leaves from the morning dew and lessen the chance of disease. If possible, orient your bales so they face north-south. This makes the sun hit them more evenly.

The strings of the bale should be on the sides, not on the top or bottom. If you look at the non string sides of the bale, you will notice that one side of the bale looks like the straw is folded; the other side looks like the straw has been lined up and cut off. Place your bales with the cut ends of the straw facing up. The water will go down in the cut straw to saturate the bale and drain.

Conditioning The Straw Bales (10-14 days)The straw bales need to be conditioned before you can plant in them. This means that you start getting them to decompose. This conditioning is accomplished with the help of lots of water and high nitrogen fertilizer. During the conditioning period, the few seeds that exist in the bale may sprout. You can pull these seedlings.

Granulated fertilizer has three numbers on the bag, such as 27-0-3. The first number is the percentage of nitrogen; the second is phosphorous, and the third is potassium. Purchase fertilizer that has the highest possible first number and low or 0 for the second and third numbers. Nitrogen speeds decomposition, which is needed to get the straw bales "cooking." As the straw starts to decompose, the bale will actually generate heat. To speed up the process, you can also use urea which has a 46-0-0 composition.

Days One, Three, and Five of ConditioningApply 1/2 cup of high-nitrogen fertilizer over the top of each bale. Water the bale until it is thoroughly waterlogged and water runs out of the bottom. You might want to pour five gallons of water over the bale, wait an hour, then repeat the process until the bale is completely soaked. Some water may run out the sides, but it is not critical that the sides be wet. Fill the buckets for use the following day.

Days Two, Four, and Six of ConditioningWater the bales again, soaking them good. If you fill the water buckets the day before, the water will be warmer and keep the micro bacteria from slowing down -- but it is not necessary for success. Do not add fertilizer on these days. By day six you might notice a slightly sweet aroma coming from the bale. This will disappear after several days.

Days Seven through NineApply 1/4 cup of fertilizer to each bale and water the bales thoroughly. Note that you are cutting the fertilizer in half, but applying it every day.

Day TenApply 1 full cup of a balanced 10-10-10 general garden fertilizer and water the bales thoroughly. By this time you will see channels developing in the bale from water drainage. Try to force the water and fertilizer into the non-channel areas so the fertilizer is distributed throughout the bale and doesn't just wash through.

You will know that the bales are conditioned and ready to plant when the bale is warmer than the surrounding soil and air, is weed-free (you have pulled all the green sprouts), holds plenty of water but drains the excess easily, and you can easily grab a handful of straw and pull it out. If the weather is colder where you live, you may have to condition the bales an extra few days.

Planting TimeThe easiest way to get a straw bale garden stared is to plant pre-started seedlings. The number of plants you can insert into each bale is as follows:

Tomatoes 2-3 seedlings per bale
Peppers 3-5 seedlings per bale
Eggplant 3-5 seedlings per bale
Cucumber 3-5 seedlings per bale
Zucchini 3-5 seedlings per bale
Squash 2-3 seedlings per bale
Pumpkin 2-3 seedlings per bale
Bush Beans 4-6 seedlings per bale

It has been suggested that root crops do not do as well in the bales, but I'm going to try onions this summer anyway. The taller plants also like corn are too top heavy. You can also grow herbs or flowers (12" or less in height). Just space them as you would if planting them in the ground. Some people also plant flowers around the outside of the bale, either on top or at a 45 degree angle in the sides of the bale -- and vegetables on top in the center. Marigolds are thought to help keep garden pests at bay. Petunias cascade down the sides of the bales and add color.

Once you are ready to plant, use a hand trowel (or just your hand) to open up an area large enough to insert the entire root mass easily. You may need to pull out some of the straw to create a hole. Make certain to remove the pot, even it it is a peat pot. Use a small amount of potting soil to make sure the roots of the seedlings are well covered and the area around them is filled. Water the seedlings immediately to seal in the roots and get rid of any air spaces around the roots.

Staking Your PlantsTomatoes and taller plants will need to be staked. If you set your bales on grass or dirt, you can pound a five or six foot stake into the ground at each end of your straw bale rows. The stakes should be buried at least a foot. Then run a wire from one stake to the other, zig-zagging it back and forth to create a trellis to support vines or heavier crops. The stakes will also help to hold the decomposing bales together. You can also stake the plants individually by driving stakes through the bale and partway into the ground for added support. Then tie your plants to the individual stakes as you normally would. Pumpkins, squash, and cucumbers will trail over the sides of the bales. They will also wander along the ground so make sure you leave enough space for the plants to spread out.

Care of the Straw BalesWater your straw bales early in the day if possible, to allow the leaves to dry as the sun comes up. A great way to water is to run a length of soaker hose back and forth across the top of the bale. Use lengths of stiff wire as a large staple to pin them down to the top of the bale. You might want to think about purchasing an inexpensive water timer so you can automatically water the bales for 20-30 minutes several times a week. You cannot really over-water a straw bale since any excess water will drain through. To tell when the bales need water -- poke your finger into the bale. If it feels dry, it is time to water.

Every 2-3 weeks, use a liquid fertilizer such as Miracle-Grow on your bales. Mix it at half-strength for the first couple of uses. You can also sprinkle granulated 10-10-10 garden fertilizer on top of the bales, or use compost.

End of the SeasonBecause of the extra heat generated by the decomposing of the straw in the bales, the plants will mature faster than they would if planted in the ground. Harvest just as you would otherwise.

The straw bales will only last one season. When you are finished harvesting your vegetables, simply pull the plants out, cut the strings on the straw bale, toss in some fertilizer, water well, and stir the straw. Over the winter the straw bale will compost down into mulch. Next spring you can spread the mulch around your garden, mix it in flower beds, or mulch existing plantings around your house.


1 comment:

  1. Thanks very much for posting this!