The Lasagna Gardening method is a tempting proposition from a labor-saving perspective. In the garden, it eliminates tilling and digging, and makes weeding a breeze as weeds easily pull out from partially decomposed materials. On the composting side, it eliminates turning required when maintaining a compost pile as well as harvesting of finished compost. It is not perfect, however, and does deliver some challenging moments just as all gardening methods do.
A Plant Has Fallen Over onto the Ground
If a plant that normally grows straight up seems to be growing horizontally, the plant may not have rooted well enough to stay in the ground. This is definitely the case if the roots are pulled up on the side opposite the direction in which it is growing. Uprooting is more common in areas that experience high winds, and with plants that tend to be top-heavy.
Supporting the plant with one or more plant stakes may resolve the problem. I find that that added bit of support is all most plants need. For larger plants such as fruit trees, I have read that some people use stones to anchor the root system. I have never tried this nor discussed it with someone who uses the practice, so I can’t personally recommend it. If you have personal experience of anchoring roots in this way, please leave a comment telling of your experience.
If you don’t want to stake the plant, either reinstall it deeper into the material of the bed it is already in, or reinstall in another, deeper bed. Use more soil, compost, and well-decomposed materials rather than fresh organics around the roots.
Watering Enough, But Portions of Bed Contents are Still Dry
If you water Lasagna Beds but the water does not penetrate throughout the bed, there may be organic materials shedding water as they were created to do, thereby diverting it out of the bed. For instance, if you put a layer of whole leaves, particularly a layer of whole glossy leaves, in the middle of the bed, the water may be reaching those leaves, then traveling along the top of the horizontal layer of leaves and draining out the side of the bed. Chopping leaves before adding them to the bed will help to prevent this. Try breaking up the leaves that are there to resolve the existing problems. Mix in more compost or soil to increase water absorption.
Do not leave roots exposed. Fill in with soil or compost if available. If not, fill in with chopped or shredded organic materials.
Think of the last time you built a three-foot-square batch compost pile that yielded about a third of that volume in finished compost. That is the rate at which the organic materials available to you loose volume in the climate where you live. Material in your lasagna beds will not loose volume that quickly because they don’t benefit from the mass, turning, and C:N ratio of a hot batch pile. However, lasagna beds will lose volume and probably do so faster than you expect.
Some plants seem to move in conjunction with the bed as the surface recedes, so that you wouldn’t notice the bed materials are losing volume unless you had edging or some other way to measure the height of the bed. The early roots are probably being compacted but new roots are growing as well. I find that vegetables and small flowers are usually in this category.
Other plants will “stand their ground” while organics decompose around them, exposing their roots. This is usually the case with established bushes whose root system is more woody. I haven’t yet determined if this condition is a result of the type of plant or if it is a result of the materials in the bed. It is possible that some materials decompose so quickly the plants can’t adjust, and others decompose at a more palatable pace. At any rate, it is best to continually add additional chopped materials on top of the bed and keep an eye out for exposed roots.
Lasagna Gardening was created by Pat Lanza, and full details can be found in her books on the subject.
Mary Tynes, Master Composter, www.mastercomposter.com