Question Re: bulb potting compost

J.E. Shields
Sun, 26 Sep 2004 12:08:34 PDT
Hi all,

Now I'll show you how much opinions vary by coming out and flat 
contradicting Roger.  Never ever use any garden soil in a bulb potting mix!

In fact, it all depends firstly on what genera and species you are trying 
to grow.  Then it depends on your climate.  In addition it depends greatly 
on whether you are a compulsive over-watering gardener or a limited or 
careful waterer.

I grow and have grown over the years, wild Hippeastrum species native to 
South America.  They are mostly from arid areas, and even those native to 
Brazil's Atlantic Rain Forest area need a dry period.  Add garden soil, and 
they will simply rot away for you in a humid climate.  They do not tolerate 
the fungi and bacteria supported by common dirt and by organic 
residues.  The same things apply to many South Africa bulbs.

So let me repeat:  If you have a rare or valuable bulb, do NOT use any 
garden soil in your potting mixes!

Jim Shields
in usually wet, hot, and humid central Indiana where we are in our 6th week 
of relative drought.

At 05:30 PM 9/25/2004 -0700, you wrote:
>On 25 Sep 04 at 11:31, Lee and Scott wrote:
> > Question:
> > Is there a page/source/website, on which one can find the "formula"
> > or "recipe" for planting bulbs in pots and the technique for
> > over-wintering the bulbs in the pots?
>That's a very interesting question. I suspect that you would find
>each potted-bulb fancier has his or her own recipe, and may even use
>different recipes for different bulbs.
>The cardinal rule is that your mix *must* (MUST!) use ingredients
>that are readily available in your area. For example consider the
>famous John Innes potting composts, as they are called. It's an
>English formula and uses the infamous "Cornish silver sand", which I
>believe is hard to come by even in the UK these days. There's
>absolutely no point trying to slavishly follow that formula. At the
>same time, if you think the John Innes mix is what you want, you can
>utilize locally available ingredients to give a similar -- by
>no means identical -- result.
>In addition, the type of mix you use depends on factors like the
>yearly patterns of rainfall and temperature, the kind of pots you
>want to use, and the bulbs you want to grow.
>Or, to put it another way, what I use in zone 8 on southern
>Vancouver Island will include ingredients you will find impossible
>to buy, and probably won't work as well for you anyway.
>And Jane McGary, about 300 miles south of me, but inland instead of
>on the coast, at a higher elevation, and in a region where volcanic
>effluvia are dirt common, will use a different mix from mine.
>Some suggestions: use a soil-based mix, not a soilless mix based on
>peat. Be careful to test the pH and adjust it using agricultural lime
>or ground limestone. (Dolomite is not as effective for adjusting soil
>pH as it is much less soluble.)
>As for overwintering potted bulbs, since you are in
> > Wiarton, Ontario.
> > Zone 5a/5b
>I cannot offer any advice except this: don't let them freeze through!
>Rodger Whitlock
>Victoria, British Columbia, Canada
>Maritime Zone 8, a cool Mediterranean climate
>on beautiful Vancouver Island
>pbs mailing list

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

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