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Fertilizer Balls


Fertilizer Balls

How do I make fertilizer cakes?

Bruce Baker answers:

I've made hundreds of pounds of fertilizer cakes---known more commonly in the bonsai
world as "poo poo balls". In fact, I now go through a couple hundred pounds of it per year. There
are recipes for these in several books, including John Naka's, but I can give you a couple of
pointers that will make it easier for you.

To start with you will need the following ingredients:
4 parts cottonseed meal,
2 part blood meal,
1 part bone meal,
some form of liquid fertilizer,
trace elements if your liquid doesn't have them.

I start with fifty pound bags of cottonseed, but unless you also have a huge collection you can
start with a five pound bag. You will also need a mellon baller, unless you like to get your hands
sickeningly dirty.

Step 1--Mix all of the dry ingredients and set aside what you don't need at the moment.
About 2/3 of a standard sized bucket of dry ingredients produces enough poo poo balls to
fertilize about 100 medium to large bonsai. Store leftover dry fertilizer in an airtight container for
later use.

Step 2--Put the equivalent of a single application into a bucket. Separately mix liquid
fertilizer to add to the mixture. I've used liquified kelp and inorganics like Rapid Gro, etc. Add
trace elements (you can get concentrated trace elements at good nurseries) if you don't use a
liquid fertilizer that already contains them. Add the liquid to the solids and stir until you have
something with about the consistency of oatmeal cookies ready to cook.

Step 3--Use the mellon baller to scoop the balls directly onto the bonsai soil surface. You
need to apply a bit of pressure against the side of the bucket to get them to stick together.

That's all there is to it. I put on a new application about once a month.

Here are all the things that have been recommended by others that I don't do and why:

1.Don't mix more than you need! If you do this I guarantee you will have a nasty problem
drying it. It will stink, mold, and attract maggots and other repulsive insects no matter how much
Sevin, or other insecticide, you use. In fact, maggots seem to thrive on Sevin-treated poo poo
balls if they dry slowly enough. If you apply untreated balls directly to the soil surface, they will
dry very quickly without stink or mold and best of all, without insects. Ask anyone who
recommends Sevin if it really works.

2.Don't use binders like flour and corn starch. This just doesn't serve any useful purpose.

A final point is that although I am a big believer in organic fertilizer for bonsai, I supplement this
with inorganics on a regular schedule. The combination results in stronger, better colored trees.

Bruce Baker

And Hud Nordin answers with:

Recipes vary, but here's one from John Naka's "Bonsai Techniques":

2 parts of cottonseed-meal
1 part of blood-meal

add water to a texture about as soft as an ear lobe. Not too dry or too soggy. Form into a small
ball about the size of a ping-pong ball (1 heaping tablespoon). Flatten each one to 1/2 inch thick
and place on the surface of each bonsai.

Some folks add some fish emulsion. You can use other seed-meals, like rape seed. Some
recipes call for letting the whole mixture, maybe with a little more water at first, ferment until
enough water has evaporated for it all to become a paste again. You need a big yard for this; it's
pretty stinky and you'll want it far from the living quarters.

Heck, here's another recipe, from Deborah Koreshoff's "Bonsai":

3 parts soya bean meal,
1 part blood and bone,
1 part chicken manure,
1 part wood ash,
1 part fish emulsion.

Put all the ingredients into a container at least 4 times the volume and add water to reach a little
over half-way up the container (don't fill the container completely while fermentation takes
place, as the liquid may bubble over--also, it is a good idea to keep the lid on during this time).
When fermentation has stopped (in about 3 months time) then top-up the bin with water and
when the mixture settles, use one part of the liquid to five parts of water. [...] An alternative to
liquid fertilizing is to make fertilzer cakes. To do so, make the same mixture as above, but use
less water, or allow the water to evaporate. When it reaches a thick consistency, add enough plain
flour to make it sticky. Form this mixture into small biscuits or cakes and dry in the sun. The
cakes are simply placed on the surface of the soil and a little fertilizer leaches out into the pot
each time the bonsai is watered. Put four, one in each corner, in a large bonsai pot, two in a
medium sized one and one in a small bonsai pot.

Uhh, make sure you have some rubber gloves for when it comes time to form the cakes!
Yuck. Oh, and don't panic if you see some insect larva enjoying the fertilizer cakes, or some
mold; that's just nature's way of letting you know your recipe is nutritious and delicious. I saw
one recipe that added a little insecticide to make it less palatable to creepy crawlers. I don't do
that because then the possum-biscuits (well, the possums think they are) might harm our
marsupial friends.

Hud Nordin