New Fall Projects Planned
and a November Virtual Violet Show!
New Interviews being adding all summer!

Soil Additives

The standard potting mix is a 1:1:1 ratio of perlite, vermiculite, and peat. However, that is not the only way a potting mix can be made. Because climates, prices, and preferences vary from person or person, it may be beneficial to "tamper" with the standard recipe to suit your own needs. Keep in mind that African Violets like moist, but not water-logged, potting medium and a light medium such that roots can easily grow throughout.

Below is a list of ingredients that Violet Voice growers have used for a potting medium.

Alfalfa Meal - fertilizer

Bark - Aeration; some water-holding capacity. Decomposition may remove nitrogen

Bat Guano - fertilizer

Blood Meal - Organic source of nitrogen

Bone Meal - Organic source of phosphorus, calcium and a little nitrogen; makes soil less acidic

Calcined Clay - moisture retention, drainage, aeration and promote root penetration in heavy clay soils

Charcoal - "sweetness"/freshness of soil

Coir - moisture retention; does not break down

Compost - water retention, anchoring, and nutrients. Quality can vary greatly depending on source. May contain beneficial soil bacteria, as well as harmful ones

Cottonseed Meal - Organic source of nitrogen, lesser amounts of phosphate and potash; acidifies soil and stimulates beneficial bacteria

Decomposed Granite - aeration

Dehydrated Cow Manure - fertilizer

Dolomite Lime - Provides calcium carbonate and magnesium carbonate, elemental calcium and magnesium; corrects overly acid soil. Not useful if hard water is used.

Egg Shells - nutrients, esp. calcium

Fish Emulsion - fertilizer

Granite Chicken Grit - aeration

Green Sand - AKA the mineral glauconite, source of potash, iron and other minerals (phosphate, calcium, magnesium, sulfur, boron, manganese and zinc).

Kelp - fertilizer

Marathon - systemic insecticide ( Imidacloprid )

Peat Moss - add some wieght to soil when wet; holds water; difficult to re-wet when dry

Perlite - for aeration; does not absorb water; According to Rob's Violet Barn, up to 50% perlite can be used when wicking

ProMix - Commercial soiless potting medium containing mostly peat and perlite

Pumice - aeration

Sand - weight; does not absorb water but holds it between grains; formerly used often to start leaves

Styrofoam - for aeration; does not absorb water

SuperPhosphate - Provides phosphate, good for roots, stems, blooms and fruit.

Vermiculite - increases aeration; absorbs some water

Vinegar - mainly added to water; makes more acidic/corrects alkaline pH

Worm Castings - fertilizer

The above information was distilled from the thread: Ask Dr. FHill ... Potting Medium and Wettness on the MSN Violet Voice.
Compiled by Rebecca.