Soil amendments are added to a
planting medium in order to provide plants with various
Guano. Dried poo. May be either from
bats or birds. Guano is available in high Nitrogen, high
Phosphorous and balanced formulations. Guano will burn
your plants, so use conservatively.
Castings. Worm poo. An excellent source of
micronutrients. Also, a supplemental source of Nitrogen.
Castings ought to be in every soilless mix. They will
not burn your plants, and, when cut with perlite and
vermiculite, make a fine medium in their own right.
Bone Meal. As the name implies, this is ground
up bones from the slaughter house. Bone meal provides
phosphorous. Will attract animals to your grow if used
outside. Will attract pets if used inside.
Meal. Again, made from animal blood on the slaughter
house floor. A source of nitrogen. Also, attracts
animals to your grow. Particularly odiferous. Blood meal
will burn your plants, so use conservatively.
Kelp Meal. Made from dried and ground seaweed.
If made from ascophyllum nodosum, provides a growth
hormone which promotes rapid growth of both roots and
foliage. Also contains trace elements and enzymes.
Perlite. A non-porous volcanic byproduct,
perlite is pH neutral and improves the drainage of
Vermiculite. A porous volcanic
byproduct, capable of nutrient and cation exchange.
Dolomite lime. Frequently used in planting
mediums to offset acidity, that is, lime raises pH.
Dolomite lime is slower acting and more buffered than