What is in leaf mould?
Myths about leaves and leaf mould
The claim that oak leaves contain high levels of tannins is true, but that this is bad for plants is pure nonsense! We have composted many loads of oak leaves and the plants grow very well on them. Even in potting soil made from pure oak leaves, the plants thrive! Another claim is that leaves acidify the soil. If only it were true! Year after year, we have the mature compost from the leaves tested and the pH always comes out above 7, which is too high for potting soil. However, as the decomposition process continues, the compost becomes slightly acidic, with a pH of around 6.5. If you use this in the garden, both as a soil improver and as a mulch layer, it will have no effect whatsoever on the pH of the existing soil.
Properties of our leaf mould
The leaves come from the surrounding area: the nearby cemetery, (former) barracks grounds, campsites and parks. But also from leafy roads with little traffic and where no gritting (with salt) has taken place. It is a mixture of beech and oak leaves, the two tree species that grow most here. We take great care to ensure that the leaves are clean, but we cannot prevent you from occasionally finding cans or packaging material. After 2-3 years of composting, it becomes a beautiful, loose material that is teeming with soil life. We use it to make our own potting soil and the Skal approves this, which says enough about the quality.
We cannot provide fixed nutrient values, as the composting process varies from year to year. This is due to the moisture content of the leaves supplied and the temperature during composting. However, as we have the soil sampled regularly, we can make a good estimate:
The pH fluctuates around 7, which means that our leaf mould is not acidic. So do not add lime! After six months in your garden, it will be between 6 and 6.5.
N. Nitrogen: The total nitrogen content of the soil is high, but not all of it is readily available. In some situations, it is advisable to add some extra nitrogen, for example with Innogreen Growth.
P. Phosphorus: The soil phosphorus content is very high. It is unnecessary to supplement this.
K. Potassium: The soil potassium content is high. It is unnecessary to supplement this.
Mg. Magnesium: The total magnesium content is high. There is sufficient magnesium available.
Trace elements: The values of most trace elements in the leaf mould are good. Those of iron, manganese, cobalt and selenium are too low. Lava granulate is very rich in trace elements that can be used to remedy a deficiency. The above values are based on plants growing in pure leaf mould, i.e. in potting soil. A 2-3 cm layer in the garden will not remedy a deficiency of a particular nutrient. Organic fertilisers in granule form are very suitable for this purpose. We have a wide range of these in stock.
