Saving Water In The Garden: Everything But The Kitchen Sink

veggie bed - raised hugelkultur ollas

This new vegetable garden bed incorporates everything I’ve learned about gardening in Houston in one place.

Raised Bed

The raised bed creates the perfect growing environment for growing vegetables in Houston. Veggies don’t like dense clay soils or flooding during heavy rains. The raised bed provides a “container” for the perfect garden soil in it and has great drainage so roots won’t rot.


Traditionally, Hügelkultur is as the practice of mimicking the nutrient and moisture-rich environment of a forest floor. Garden beds are built over large, woody material and leaves. The decaying wood and plant material inside the bed is a gold mine – providing nutrients over time to feed the plants and holding excess water that can be used by the garden during drier times.  Hugelkultur reduces/eliminates the need for fertilizing and irrigation.

Wikipedia defines Hügelkultur as:

The practice of making raised garden beds filled with rotting wood. It is in effect creating a Nurse log, however, covered with dirt. Benefits of hugelkultur garden beds include water retention and warming of soil. Buried wood becomes like a sponge as it decomposes, able to capture water and store it for later use by crops planted on top of the hugelkultur bed. The buried decomposing wood will also give off heat, as all compost does, for several years. These effects have been used by Sepp Holzer for one to allow fruit trees to survive at otherwise inhospitable temperatures and altitudes.

I put dead tree limbs, dried leaves and compost at the bottom of the new garden bed to provide a reservoir of moisture, warmth and nutrients for the vegetables planted there.


Ollas are unglazed, single-fired, clay pots that are burried in the soil. The pots are porous, so water passes slowly through the walls and seeps at a constant rate that provides consistent moisture to the adjacent soils and plants. This method of irrigation is very efficient because the water goes right where it’s needed, to the plants roots, without loss through evaporation.

I used 2-gallon Dripping Springs Ollas in the raised bed to provide underground irrigation and consistent soil moisture in the bed.  Each olla provides water for a 36″ circle, so I placed 4 ollas in the 6-foot by 6-foot bed.

Concrete Blocks

Building a raised bed with concrete blocks provided insulation and a second growing environment. When the concrete blocks are filled with garden soil, they provide “insulation.” Water evaporates more slowly through the sides of the bed because there is another layer of soil and concrete that water has to pass through before reaching the air and evaporating. This keeps  the soil inside the bed moister for a longer time.

Each hole in the concrete blocks makes a little “pot” where the soil dries out faster. These holes are great for growing herbs and flowers that like good drainage. The lime in the concrete makes the soil in these holes more alkaline…great for plants like strawberries.

This new bed can support dense planting. Here’s a picture of what’s growing in the winter garden.

raised garden bed - planted