On 11/5/2016 10:31 AM, Hypatia Nachshon wrote:
Looking for an organic rose food, I found this from American Rose Society.

http://www.rose.org/rose-care-articl...s-when-and-how

1 cup bone meal or superphosphate 0-20-0
1 cup cottonseed meal
1/2 cup blood meal
1/2 cup fish meal
1/2 cup Epsom salts (magnesium sulphate)

They say that's a basic recipe PER BUSH??!!!

Some of my bushes are not very big (maybe because I have been only
intermittently feeding them commercial Rose food?) but that quantity
per bush seems like overkill.

Experience/opinions appreciated.


Most roses are hybrids that do not exist in nature. That is, they are
unnatural. Thus, I do not use natural or organic fertilizers on them.

The first feeding in the spring -- just as new shoots start to show --
consist of the following per plant:
1 handful of ammonium sulfate
1/2 handful of iron sulfate
2 large pinches of Epsom salts (magnesium sulfate)
1 very large handful of gypsum
Roses thrive with an acidic soil all of the above contain sulfur,
including the gypsum (calcium sulfate). Except for the gypsum, which is
neutral, that means they are acidic.

The next feeding a month later is with a commercial fertilizer that
contains a systemic insecticide. Thereafter, I feed my roses monthly
through October, alternating between just ammonium sulfate and the
commercial fertilizer.

If you want to go organic, note the following.
* Superphosphate is NOT organic. It might be from natural sources; but
it is not derived from living matter, which defines "organic".
* Applied to the soil surface, bone meal or superphosphate will not feed
your roses. They are both sources of phosphorus, which does not leach
through the soil. Instead they must be placed down into the soil where
plant roots will find them. About once in 10 years, I take a length of
steel rebar and poke 3-4 holes around each of my roses about 1-1/2 feet
away from the base. The holes go 1-2 feet deep. I fill the holes with
superphosphate. It will last about 10 years and will be where rose
roots will find it.
* I think the American Rose Society's recipe has far too much Epsom
salts. 2 tablespoons per year should be more than sufficient.
Magnesium is considered a trace nutrient. It promotes new shoots, which
are good if they are from the bud union and are bad if they are from the
roots.
* Cotton seed, blood, and fish meals are all good sources of nitrogen.
They release nitrogen slowly and might be needed only 1-3 times a year.
The amounts thus seem reasonable. My use of ammonium sulfate is also a
source of nitrogen but released quickly, which is why I apply it more
frequently. Roses need abundant nitrogen, which is often lacking in
southern California soils and is thus the primary factor here in
limiting vigor in rose plants.

Note that fish and blood meal might attract raccoons, possums, dogs, and
cats. I have recent problems with some animal digging up new plants
where I stirred bone meal into the planting hole. They do not eat the
plant but dig deeper, apparently seeking meat after smelling the bone
meal. I know that dogs cannot get into my yard; but I have seen cats,
raccoons, and possums in my yard.

--
David E. Ross
Climate: California Mediterranean, see
http://www.rossde.com/garden/climate.html
Gardening diary at http://www.rossde.com/garden/diary