PROPAGATION MEDIA Definition these are natural or artificial

PROPAGATION MEDIA Definition – these are natural or artificial media used for a propagation purpose. They can be manipulated for the intended use (germination or grow-out) ØThis should be cheap and easily available ØAllow for easy removal of propagated plants ØCan be soil and soil-less media

SOIL MEDIUM/MEDIA n n Soil media are those mixes that contain some proportion of soil (true soil material) Consist on mineral elements Dense and bulky Can be added to other materials to formulate a soil mix (2: 1: 1)

SOILLESS MEDIA n n Contains various combination of the natural or synthetic non soil materials. Use in proportions that mimic the environment that a natural soil would provide for a seed or plant. Can be manipulated to create a wide variety of growing conditions not available in nature. Such as; Perlite Vermiculite Peat Moss Grit Sand Coir waste Sphagnum Moss Slow release fertilizers

ADVANTAGES OF SOILLESS MEDIA n n The mix is uniform; does not vary in fertility, acidity (p. H) or texture. Sterile - containing no disease organisms, insects or weed seeds. Soilless mixes are lighter in weight, and thus easier to handle and ship. Good moisture retention and drainage are possible through the proper combintion of ingredients.

Advantages n n Convenience of use – ready to use when purchased Versatile – can be made to order (custom mixed) for specific needs. Can amend soils or soil mixes.

DISADVANTAGES n n Limited nutrients - since the mineral content in most mixes is low, minor plant food elements necessary to plant life may be missing. eg. Iron, sulfur, manganese, zinc, calcium. Light in weight – easily toppled over by gentle wind or push (when used in trays or pots).

Sphagnum Moss n n n Consist of partially decomposed dehydrated plant material Different degree of decomposition form the basis of the material grading High moisture and nutrient holding capacity Recovered from acidic bogs The grades used in horticulture have a p. H between 4. 0 and 4. 5

Sphagnum Moss n n n Its is light in weight and relatively disease free Inhibits the growth of organisms responsible for damping-off diseases in seedlings Can be pasteurized without being destroyed

Wood By- Products n n n Wood shavings and saw dust may be used in soil-less mixes However the source is important since some woods such as redwood contains high levels of manganese, an element injurious to young plants Leaching helps to remove the toxin in these woods

Wood By-Products n n Sawdust from cedar and walnut should also be avoided Leaching is ineffective in removing toxins Also create temporary nitrogen deficiencies. Sawdust when used, need added nitrogen

Useable Plant By- Products n n Peanut shell Bagash (from crushed sugar cane) Straw corncobs

Bark n n n Bark from hardwood such as maple and oak and softwood such as conifers can be used in a mix. Hardwood barks are higher in nitrogen, phosphorous and potassium Lower in calcium when compared to softwood bark

Soft wood n Higher in micro-nutrients, esp. manganese

Barks n n Growth inhibitors have been found in the barks of walnut, cherry, cedar and white pine. Slash pine do not contain growth inhibitors

Disadvantages n n Lack field correspondence – constituted to provide minimal problems to germinating seeds and rooting plants. Costly – some mixes are expensive

Properties of a Good Mix n n n n Drain freely (good Infiltration) and well aerated. High particle stability (should decompose rapidly) and easily wetted Good moisture holding capacity and bulk density mix should be able to flow easily Should not produce toxins Have good CEC and buffer capacity Pasteurized to kill pathogen Adequate nutrients for plant growth and development

Materials use in formulating a Mixsoil-less mix Materials of plant origin n Peat Moss – inorganic material composed of partially decompose plant material preserved under water. n Recovered from underneath bogs and swamps n Have high water holding capacity n Supplies some nutrients esp. nitrogen (1 %) n Low in phosphorous and potassium

Peat Moss n n Types differ according to plant material acidity and degree of decomposition Best and most widely used is sphagnum peat.