Identifying Soil Requirements
Many trees and shrubs grow on a wide range of soils. Soil requirements for different plants vary and the soil has to be prepared before the planting takes place. For example, when you are planting a flower bed, the digging has to be deeper (almost 2 feet) than when you are planting a lawn.
Lumps should be broken and sand, cinders and ash should be spread in the bottom soil. Manure, compost, grass clippings and peat moss could also be worked into the bottom soil.
The soil also requires that the top layer should be made ready for planting. The topsoil, therefore, should have a layer of good loam such as humus, peat moss, green manure and leaf mould. Wood ash, and sand are used as and when required by the soil. Lime loosens the soil, and so can be used when required.
A word of caution regarding the use of manure – care should be taken that it does not touch the roots of the plants. Soil testing kits are available in the market which can be used to test the soil in your garden. On the pH scale, below 7 means the soil is acidic, and above 7 means that the soil is alkaline in nature. Many of the garden plants like rhododendrons, azaleas and many types of heather prefer a little acidity in the soil, around 6.5.
How well the plant grows is directly linked to the or alkalinity of the soil. Plants need specific amounts of Nitrogen, Phosphorous and Potassium to grow. Since these are directly absorbed from the soil, it is necessary to know what kind of soil you have, and if necessary add leaf mould or peat to the soil to make absorption of these minerals possible. The optimum pH value should be in the range of 6 to 7.5. Below 6, Nitrogen, Phosphorous and Potassium are not so easily available for absorption. Above 7.5, Iron, Manganese and Phosphorous are not easily available for absorption. Addition of compost and mulch adjust the pH value of the soil.
It is always a good idea to add organic matter to the soil rather than chemicals because organic matter neutralizes both the acidity and alkalinity of the soil. Points to be remembered are, that if your soil is too acid, you will need to add ground limestone. Allow for it to be absorbed by the soil, then your soil will be ready for planting in the new season.
Wood ash also raises the pH value of the soil. Because it is powdery, it will be absorbed faster. Pine needles, shredded leaves, sulphur, sawdust and peat moss lower the pH, i.e., if your soil is too alkaline, using these will make the soil more acidic.