Setting a Good Foundation
The Importance of Soil and Drainage in Japanese Gardens
Drainage:
The foundation of a good Japanese miniature garden depends a lot on the drainage pattern. If you are creating a garden in a trough, then slope the bottom of the trough towards the drainage holes. Cover the drainage holes that are inside the trough with one or two broken china pieces, broken earthenware flowerpots or crocks. Make sure that the pieces are large enough not to fall through the holes. Place them in a manner that they do not move out of position. It is always better to have the concave face of the crock on the top. Place a layer of pebbles, small chippings or broken crockery pieces at the bottom of the trough. You can also use washed gravel or clinker, avoiding any material that tends to hold surplus water or clog.
Soil Foundation:
A layer of horticultural peat, sphagnum moss or leaf-mould can be placed over the drainage layer in your Japanese garden. The cheaper alternative is coconut fiber, dead leaves or old turf. Check all the material before you place any in the trough. Remove all the extraneous material like roots, twigs, larvae, seeds, insects and worms. Ram this layer firmly, so that the edges and corners are well packed. This layer will help the soil to retain the desirable amount of moisture and also prevent it from being washed away.
Soils to Suit Plants:
Soil can be affected by various factors. It can be affected by a number of chemical, natural and human agents. Since different groups of plants have different requirements, the soil used for one plant may not be suitable for another. Chalky soil suits most of the lime loving plants that may include a variety of rock and alpine plants. Sandy soil can be acidic and it is favorable for several corn and bulb plants, some conifers, heathers and flowering shrubs. Porous clay soil is perfect for rose trees and flowering shrubs. Peaty soil is suitable for shrubs and moisture loving plants. The ordinary garden soil is called loam and is a combination of clay and sand, often enriched with humus. Loam is extremely variable in quality and is a “basic” soil that suits almost all plants. For instance, you can add lime couk for lime loving plants. Many people who have created Japanese miniature gardens have been successful in using sifted loam as garden soil.
Compost:
Good quality compost is a little costly but it is worth the money for rare and expensive plants in your Japanese garden. You can buy compost that is “ready-for-use” or you can mix it to suit the soil type. Nursery workers are equipped to help recommend a suitable mixture or formula. The base formula of regular compost is usually three parts of sterilized soil, one part of granulated soil and one part of coarse sand, preferably silver. Adjust the proportions according to the plants. Other ingredients like grit, hydrated lime or fertilizer can also be added. If you are an ambitious gardener, then there are chances of “trial and error,” but at the end of the day you will learn valuable and unforgettable lessons.
Filling the Japanese Garden:
Prepared compost or soil can be layered over the peat and water can be sprinkled. The layer needs to be rammed down firmly. The next layer is where the stones and rocks are set. Use the same soil mixture and firmly press it down. There are chances of the soil level subsiding in the first week.
Top dressing:
When the “operational layer” is complete, a light top dressing of bone meal can be dusted over the surface, along with a sprinkling of very fine and clean chippings of limestone or granite. It will help to prevent the erosion of soil by wind.
Filling the Dish Garden:
Porous earthenware is the best type of bowl or dish for a Japanese miniature garden. You can arrange for the earthenware dish to be fitted inside a decorated container. Ideal small containers have drainage holes that are filled in a particular manner. It is good to cover the bottom of the dish with a thick layer of charcoal. The drainage layer of chipping or crock is then laid over the charcoal.