I've been adding Osmocote to planting holes along with bone meal and
alfalfa pellets for 5 years with good results. We plant bareroots here
while the soil is still too cold to release very much nitrogen or other
nutrients from a coated fertilizer. In fact, that is why I apply a mild
solution of water soluble fertilizer in the early spring, after all
the roses have leafed out and shown vigorous new growth. (Just did it
today: combination of liquid kelp and Growmore Magnum Rose food at
about half strength). But even when I plant potted roses in the middle
of summer I add Osmocote to the soil mix.

I doubt that adequate nutrients stunt growth; in fact, I suspect that
the contrary is true. The hard part is knowing what is *optimal*, what
is superfluous and therefore a waste of resources and what is excessive
and therefore deleterious. I've read enough about growth mechanisms in
plants to believe that more top growth stimulates more root growth and
more root growth stimulates more top growth until the plant reaches its
genetically determined size.

A bareroot rose develops feeder roots much sooner than one year. Just
consider how soon you will see roots in the drainage holes. By that
time, the feeders will have filled the 5 gallon pot. Certainly the rose
could tolerate feeding by then! IMO, waiting until then it too long.
I've watched the rate of root growth in own root roses, and it can be
considerable: from a band to filling a one gallon pot within 3 weeks.
In the spring, the 5 gallon will fill with feeder roots within 3 or 4
months, depending on the size of the rose.


Rob wrote:

I would also like to add that it is better NOT to mix in alfalfa
in de planting hole, as it might damage the roots when it
decomposes.

but how, exactly?

It's not from my own experience, but a lot of websites writing about
alfalfa say it's better not to add it to the planting hole because
the decomposing of the alfalfa generates heat. Maybe it is safe to
use in small quantities, like you state, but maybe not. To be on the
safe side, use alfalfa as a top dressing and use decomposed organics
(compost) as a soil amendment in the planting hole.

I've added it to planting holes for 5 years without ill effect. The
recommended amount is 1 cup, tho I've added as much as a quart to a big
rose hole.

I agree that quick release fertilisers and manures will burn roots,
but Osmocote and other organic types (alfalfa included) are great
in small quantities. The idea that roses would become lazy around
the presence of nutrients is an absurd concept.

Well, the part about the laziness was just illustrative. I meant to
point out that an abundance of nutrients might slow down root
formation, because there is less stimulus to spread out and search
for 'food'. Or, explained differently, if there is an abundance of
nitrogen, the plant starts to grows stems and leaves before its root
system would be the size you want it to be.

Excessive nitrogen is never good, whether you have lots of roots or
few. Adequate nitrogen for the growth stage is the best.

Also, you don't need to add fertilizers to a plant that does not have
roots yet, because it cannot absorb the nutrients.

This is true, but those roots grow fairly quickly, much faster in early
fall.

Give it a year to get the root system going and then start
fertilizing for good growth and nice flowers.

IMO, waiting a year is too long. But I am entirely in favor of
fertilizing at about half of recommended rates.