The Content Of The Article:
The passionate (hobby) gardener usually selects carefully the plants that should decorate the home and garden. Strong shoots, a healthy trunk, the most beautiful blossoms - everything is critically eyed and only the best are taken away. But just as much value as the condition of the plant should be given to choosing your home: the substrate in which to develop its roots. Of course, it often does the next best bag of potting soil from the hardware store, but for a plant to feel really comfortable and bring its best results, it takes a bit more.
And, last but not least, one should still pay attention to a pH adjusted to the particular plant, ie the concentration of hydrogen ions, which is usually between about 5.5-6 (slightly acidic) and 7 (neutral). If the value is too high or too low, it can be easily changed with the addition of various substances: so-called fertilizer lime or basic irrigation water increased, peat or vinegar z. B. reduces the pH.
The mixture makes it...
For most plants, it is easy to produce a well-suited substrate yourself. For this you mix basically 1/3 normal garden soil with 1/3 filler (peat, Cocosubstrat, sand, expanded clay, Perlite etc. ü also several in a mixture) and 1/3 well rotted compost. The more sensitive to moisture a plant is, the higher should be the proportion of fillers, it may even be more than 50% of the volume.
Here is a brief overview of the most important filling and substrate materials:
Expanded clay: Inorganic substance produced from clay beads which have been inflated during a firing process without additives, which subsequently have air pores and at the same time develop a self-contained, pressure-resistant surface. Broken expanded clay (Lecadan) is also commercially available.
- Perlite: inorganic filler made from volcanic glass; free from fungi, pathogens and nutrients and therefore also good for germination.
- Seramis: The most common drainage material. Not dissimilar to expanded clay, but with completely different properties - high absorbency, but hardly permeable to air. For breeding purposes Seramis is only conditionally usable. If a plant is set in seramis without the bale of the earth, the root neck becomes too wet - that is deadly to many plants!
- Baystrat: foam specifically for the
- Grodan: Rockwool
- Quartz gravel: is rarely used today due to its weight
- Peat: The organic material typical of moorland is found in many mixtures of soil, but its use is problematic due to its slow formation and depletion of marshes. In addition, many gardeners are mistaken if they want to improve their soil with raised peat: this deteriorates the soil rather more because it contains few nutrients and leads to acidification.
- Coconut substrate: A very loose substrate made from the coconut fibers, sold as briquettes, is softened in water before use and is an excellent alternative to traditional materials.
Special soil mixtures:
Mixtures with loam or clay:
Most of these mixtures have a slightly higher pH, which is good for palm trees and many other tropical and subtropical plants. For this purpose, a basic substrate of predominantly humus material carefully mixed with 20-40% structurally stable clay, but you can also use mixtures of compost and garden soil, since in most gardens anyway contains a lot of loam.
Strong acid soil:
A very acidic soil with a pH between 4.5 and 5.5 requires species such as Primula, Camelia, Azaleas or Gesneria. At a pH of 6, they can not absorb enough iron to form enough green leaf. Best of all, these substrates are mixed with lime clay, sour clay soil, coniferous soil or acid high moor peat.
Special case epiphytes:
There are also plants that need no soil at all, the so-called epiphytes. These grow on trees, in whose branch forks humus has accumulated, some have even tapped rocks as a habitat. Often, their roots serve purely as adhesive organs or they are completely absent, filtering water and nutrients from the dew or rain and the dust particles dissolved therein. The epiphytes include bromeliads, as well as some ferns and of course the orchids.
by Karin Fasching