Hay in hugelkultur?

I am what you might call an very small scale urban gardener. I have identified three areas where I would like to try a version of hugelkultur. Two of the three are next to the foundation of my house, and I am concerned about terminates and carpenter ants.

I've read that hay might be used in hugelkultur bed in place of wood or in addition to wood. If I dug my holes deep enough to hold bales of straw/hay, would I achieve the sponge effect for moisture.

I assume this would also be less attractive to the termites.

I've never used hay or straw in a proper hugelbeet, but I have grown plants in straw before - I have not grown in hay, specifically, so I don't know how that might differ.

The method I use is:
- Arrange your straw bales into a keyhole garden, or whatever other pattern you like, (personally, I like to stack two bales on top of each other - the first time I did this, I only used one, and the raised bed effects declined midway through the season)
- Throw some soil and/or compost on top of the straw
- Water it daily - I collect my urine and distribute that over the straw as well
- Plant your items of choice, (I've tried both seed and transplants - seeds do quite well, I find)
- Mulch your plants with fresh straw throughout the season, and if you want to continue, apply new bales over the top to decompose through the winter and deepend the resulting soil. (You can start your straw planting beds the year before you plan to plant them, this way, and get ahead of the game, but if you do that, definitely stack at least two layers of bales. I've never done more than two layers myself, so I can't comment on what it would be like using more.)

I take for granted that a hugelbeet would perform in roughly the same way.

Use straw not hay.

Hay will disintegrate in about 3 weeks if in contact with air water and soil.

Straw will hold up longer, but I think you'll find that where straw meets soil there is potential for big, fat holes. Not exactly the best place to grow things. Edge creates problems here. I recently stomped down my half-submerged straw bales after less than a year. They reduced by at least 2/3 of the mass.

I would also put extra soil on top, because all that soil is going to be coming down sooner or later, so you want to make sure you're not left with a lot of dirty straw.

Also should factor in the carbon-nitrogen situation. All that carbon in the soil needs nitrogen to balance it out, or else you'll end up with nitrogen deficient soil. Add something like manure, or urine even.

Also, straw tends to dry out. So that sponge effect you'll have to create yourself by watering if you don't get enough rain.

best of luck,
William

William,

Thanks for the input. I plan to buy straw bales, and I am not concerned by the faster rate of decomposition for the straw. When my house was built, the builder used sand as a back fill. [why? Who knows.] I am going to dig down 3 to 4 feet into the sand, so I can build a better bed to grow in. For the two spaces near the house lots of tasty wood would temp bad insects to set up a nest.

I will place a thick layer of cardboard followed by manure and some brush waste. On top of that I will place the straw bales, then more manure and other nitrogen rich stuff [like green grass] I will top it off with compost and bokashi.

Even if I have to add 50% more th the bed next year, the space should be better than pure sand . From what you have said I should not expect a long term sponge affect from the straw. Is that correct?

Not to the extent of wood but organics in the soil will add water sponging effects and decayed straw is organics. The bad news is that you can expect the area to subside for several years. The good news is that you will be creating deep rich beds and if you green mulch the upper layers as well as plant legumes for the 1st couple years they should be quite productive too.

If you're digging out the sand right next to your house I would stop if I encountered more solid material, like clay. It could be that your foundation was built properly, with clay down below, but when the house was finished he put sand there to meet the required 2% grade (positive drainage away from your house). You might improve the situation, but be careful not to pool water up against the foundation.

I share concerns about the bales drying out on ya, especially if the soil is sandy. Maybe hose them down really well before you bury. More exotic: you could leave a pipe sticking out somewhere for periodic injections of water into the middle.

Let us know how it goes.

The sand is about 4 feet deep. Next to the foundation it goes down 7 to 8 feet, the height of the foundation wall. Along the sides of the foundation at the base are french drains, pipes and crused stone which extend beyound the length of the house. In five years there has been no moisture in the basement, and the deep sump pit rarely gets water in it. At most it has been 6 inches deep, and that is still a foot from the bottom of the slab.

I have only 5000 square feet of land, and the 50 by 25 founation and driveway covers a lot of that space. The two spots near the house I want to improve will both be about 12 sq feet. They have full sun, and I plan to plant a tall blue berry bush in one and some other berry in the other. Besides the straw, there will be as much cow dung as I can burry before the winter. I hope it will be ready in the spring.

Someone may have addressed this earlier, but I would suggest placing landscaping cloth underneath any additions of organic matter to the sandy area in question. It will allow aeration and some drainage, while retaining most of the organic material - the cloth is fairly inexpensive and widely available.

I had thought about doing that, but more to try to hold the moisture in the hay layer. Keeping the organic content in place. Good idea, thanks.