How To Make Organic Fertilizer
|Organic fertilizers don't have to be
expensive, since you can make your own. If you buy the components in bulk, you'll save
Recipe For Organic Fertilizer
I've been using this recipe, which to the best of my knowledge was
created by Steve Solomon (founder of Territorial Seed Company), for six years now with
good results. One word of advice: Instead of buying the components in small boxes, buy
bulk bags (40-50 lbs.) at a farm supply or feed store. As long as you keep them dry, they
will last for many years.
This component provides nitrogen, with smaller amounts of phosphorus
and potassium. I like to use cottonseed meal, which is cheap (about $13.00 for a 40 lb
bag) and easily available. In some states, though, it is not allowed in a certified
organic operation (not something a home grower needs to be concerned about). Other options
are alfalfa meal, or rape/canola meal. Cottonseed meal has a NPK value of around 6-2-1.
Seed meals tend to be acidic, so lime is included to balance that
out. Dolomite limestone is roughly half Magnesium Carbonate and half Calcium Carbonate.
Calcitic limestone is pure Calcium Carbonate. Plants usually need more calcium than
magnesium; so, if you want to be really tricky, use 1/3 part dolomite lime and 2/3 part
Bone Meal And Rock Phosphate
These ingredients make up the bulk of the phosphorus component. Less
bone meal (NPK ~ 0-10-0) is required since it releases its phosphorus more readily. The
advantage of using rock phosphate (NPK ~ 0-3-0) is that it continues to contribute
phosphorus to your soil over many years.
Kelp meal (NPK ~ 0-0-10) contributes potassium, and also many
micronutrients. This tends to be more expensive than the other components: I recently paid
$35.00 for a 50 pound bag.