vegetative propagation TOW

Diane Whitehead
Sun, 04 May 2003 21:43:20 PDT
These notes are not from personal experience, but from notes I made 
at several workshops and lectures I have attended.  I have always 
left the lecture full of plans to propagate my bulbs, but, with the 
exception of lilies, I haven't yet done so.  I am not sure whether it 
is cowardice at actually chopping a bulb up.  Perhaps it is timing. 
Many bulbs are propagated well after flowering, and by then, I am 
busy with plants that are flowering and have forgotten the ones that 
are dormant.  Lilies can be scaled as the bulbs are being planted, so 
both jobs can be done at once.

One lecture was a dramatic one, given by Paul Christian in 1989 at a 
study weekend at Edmonds Community College near Seattle.  It was a 
wild demonstration, and I wish I could remember more details.  I 
would love to see it again.  Paul dressed as a chef, I think, and 
used big vegetables as demo bulbs so that everyone in the audience 
could see what he was doing.  A huge cabbage was twin-scaled, a 
turnip had its base scooped out, and so on.  He was whacking away 
with a machete, vegetable pieces were flying, and the stage ended up 
looking like a salad.

Here are my notes from his lecture: 

Propagate bulbs as soon as they enter dormancy.

Use a systemic fungicide like Benlate, but take care as it is 
carcinogenic. [I think this is no longer sold.  I use powdered 

Gently moisten perlite, 25 parts perlite to 1 part water.  The 
vermiculite he can buy in England promotes penicillium molds. 

Time of year and temperature interact.  You need to decide on good 
timing.  They need 65 - 75 F to form bulblets, which when rooted then 
need a cold period of 6 weeks, which can be in a fridge, to break 
leaf dormancy.  You can slice off a little bit of the scale with the 
bulblet, and then re-use the scale which will form more bulblets.  [I 
have had success by breaking off a few scales, or just gathering any 
loose scales on lily bulbs I have bought in the fall.  I put them in 
a plastic sandwich bag of damp vermiculite and put them in a kitchen 
cupboard.  My kitchen is usually about 18 C during the day, and 
cooler at night, but perhaps it is a bit warmer inside my cupboards. 
As bulblets form, I pot them when they are rooted, and put them 
outside in a cold frame ]

Narcissus  - August
The meristem is in the basal plate, at the bottom of the bulb.  This 
is where roots form.  Sit the bulb on its base, pointy end up and 
slice right down through the bulb, like cutting a round cake into 
slices.  You may get 64 slices of a large bulb, and perhaps only 4 of 
a small one.  Soak in Benlate for 20 minutes.  Put in damp perlite 
for about 6 weeks.

You can twin-scale - separate the slices so that each piece has only 
two scales.  The bulblets will be smaller if you do this.  Expect 50% 

Juno Iris
Storage root with a tiny bit of bulb.  Prone to fungal infection. 
Use powdered sulphur.  25% mortality.

The rhizome is actually a horizontal stem, with dormant buds in the 
axils along it.  If you remove the growing point, and sulphur the 
wound, the growing point will grow, and the dormant buds will start 
to grow.   You can also slice the whole rhizome in quarter inch 
slices (.6 cm), trying to get a brown growth ring on each, sulphur 
and put in perlite.  It may take a year for the buds to break.

Sanguinaria canadensis fl pl - Double bloodroot
Slice into 1 inch sections (2.5 cm) and burn the ends over a candle. 
Use Benlate.  Plant in a nursery bed.  It will take them a couple of 
years to flower.

Scoop out the large growing point, swab with alcohol and then treat 
with sulphur.

Cyclamen - I have my doubts about this.  Maybe this is still supposed 
to be notes on Arisaema.
Scoop out the growing point, which will root also.  Treat with 
alcohol because it is slimy, pack with sulphur.  May take a year. 
Then slice in chunks, each with a growing point.

Crocus  - don't usually have to propagate them, as most do well on their own.
Do this to ones that don't increase well, like sieberi Bowles' White, 
and various colour forms of banaticus.  Scoop out the top.  Sulphur. 
4 or 5 bulblets will form.

Fritillaria pyrenaica yellow form.
The bulb has two scales.  Pull it in half.  One has the new shoot and 
will flower next year as usual.  The other scale will form a new 
growing point and it will flower the next year also.

Failure:  Tulipa alba caerulea
The seed pods are extremely prone to botrytis.  Each bulb forms one 
offset per year which takes 2 years to flower.  It doesn't respond to 
any form of mutilation.  [I have noticed this for sale in bulb 
catalogues in the last couple of years, so obviously the problem has 
been solved somehow.]

Tomorrow I'll write my notes on Janis Ruksans' talks this year.

Diane Whitehead  Victoria, British Columbia, Canada
maritime zone 8
cool mediterranean climate (dry summer, rainy winter - 68 cm annually)
sandy soil

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