Roy nsson sow tt Srows EVERY spring I get inquiries from new garden- ers about what manures, composts and top soils they should be adding to their gardens. A heaithy garden soil is alive with microbial activity and contains sufficient nutrients and organic material to support plant life. Almost all plants derive their nutri- ents from the soil but the nutrients must be in a soluble form to be drawn into the roots or cell struc- ture of the plant. Being in a soluble form, the nutrients also have the potential to be washed away by rain water. This content and low in organic materi- al. They may bz no better than ny soil. Fresh manures have the poten- tial to burn newly formed or rend Hibrois roots and thereiore should he aged for ¢1 o 12 months before being used. Aging requires the manure to be turned (aerated) to prevent it from becoming anaer- obic and stored under cover to pre- vent leaching of the nutrients. Manures stored outside in the open may be a good soil conditioner but will have little nutritional value. Adding manure or compost to the soil in the fall or winter will allow excessive leaching of nutrients. The best time to amend your soil is in the spring, about four to six weeks before you are ready to plant. This will give the soil microbes a chance to break down some of the nitrogen compounds and prevent any root damage. Home compost dues not have the same potential ro burn as fresh manures and can be added to the soil at almost any time, providing it is well mixed with the soil or used as a mulch. Organic amendments do not have the concentrated nutrient val- fianure makes your garden grow robs the plant of its food supply. Sandy loams (soils with a high sand content which are common to the North Shore) have little ability to hold nutrients and water. To make a sandy loam more retentive of nutrients and moisture, add an organic amendment such as manure or compost. These amendments pruvide two other major benefits in the form of new nutrients and an ideal environ- ment for the microbial activity that is so important to plant growth. In areas where no top soil exists, it is best to bring in a supply of top soil to create new beds, seed new lawns or plant shrubs and trees. Where beds and plants are already in place but the soil has lost much of its organic content and nutrients or the level of soil has dropped, it is better to try to improve the soil with amendments rather than bring in new soil. Adding a 5 cm (2 in.) Jayer of organic material will not only raise the level of the garden bed but it will help replenish the nutrients in the mineral soil and insprove the ability of the soil to hold those nutrients. Most inexpensive com- mercial top soils are high in sand ues of chemical fertilizers. A flower and vegetable fertilizer such as 4.10.10. will contain 24% actual elemental nutrient whereas a rich home compost may be rated as 1.5.5 of a total of 2% slow release nutrient. To achieve the same nutrient value with compost it is sary to add 12 to 15 times as much material. Producing a cubic metre of home compost each year will help to renew and rebuild the soil in vour garden but it may not be suf- ficient for vour total needs. The commercially available sources of organic amendments may include animal manures, mushroom com- post (manure) and commercial compost. Steer manure from feed lots is one of the bese and cleanest sources of manure, providing it has been properly aged. Horse manure is sometimes available from local stables but often contains too many weed seeds and has too high a percentage of fresh sawdust. Chicken manure or any of the fowl manures are very high in nitrogen and should be used with caution. They have the potential to burn roots and produce excessive top growth. Remember, NEWS photo Mike Wakefleid THE best time to amend your soil is in the sering, about four to six weeks before you are ready to plant. Garden columnist Roy Jonsson says this will give the soil microbes a chance to break down some of the nitrogen cempounds and prevent any root damage. all manures and particularly fresh manures have a strong odor if not aged or mixed with the soil. Commercial compost, unlike home compost, should be treated like manure when applying. The high heating process thar it goes through makes the product virtual- ly weed free. Mushroom compost is used like a manure but is in the spent compost from the commercial mushroom barns. Often the mater- iai is sold before it is properly aged and may be too strong for immedi- ate use. Mushroom corapost may atso be coo rich in salts with a very high pH (alkaline condition). In this form it is not suitable for use where you have acid-loving plants. Worked into beds where you n mally add lime, it will add nutrients and take the place of a lime appli- cation. Home compost is usually close to a neutral pH and