Container Planting, Site Conditions and Maintenance
Container Planting
Soils modified for ornamental planting mixes should contain at least 5% organic matter. By using compost as the organic matter source, landscapers get the added benefits of various macro and micronutrients, a stabilised pH, and a supply of beneficial micro-organisms.
Planter mixes can contain up to approximately 1/3 compost. At high inclusion rates many perennial and annual species will not require fertiliser. However, gross feeders should be given additional nitrogen.
Care must be taken with some ericaceous subjects (e.g. heathers, rhododendrens). Soils above pH 6.5 will adversely affect the growth of plants requiring an acid soil. However, a lower rate of compost can be used, e.g. 10% by volume, as long as the other components in the mix are not alkaline.
Site conditions
The site drainage must be adequate before planting takes place. Subsoils may need to be ripped to relieve compacted layers. This should not be done when the soil is too wet. Plastic drainage tubes, gravel filled holes, and other methods can be used to assure proper site drainage below or around the planting holes.
Where soils are particularly low in nutrients compost may be supplemented with a nitrogen fertiliser. Nitrogen in compost is mainly in a slow-release form and may not provide enough nitrogen in the first few weeks of growth.
On-going Maintenance
In subsequent years, compost may be applied at 25-75mm depth as a mulch, or raked in to the soil, replacing the need for any additional fertilisers.
Nutrient Values
Soil Amendment - overview
Using Compost for Soil Improvement
Container Planting, Site Conditions and Maintenance
