About Crinum Seeds and Seedlings (a long missive)
ConroeJoe@aol.com (Sun, 28 Nov 2004 11:07:30 PST)
Hi,
A year or two ago I purchased some Crinum variable seedlings from Silverhill
Seeds; they germinated easily and grew well, apparently not caring if it was
summer, winter, or whatever. They enjoyed the rains and the winter
temperatures, etc.; 5 or 6 bulbs sitting happily in 1-gallon pots and growing slowly.
I got ambitious and found some C. bulbispermum seeds on plants that had
naturalized in this part of Texas. These seeds too were easy, they germinated
quickly enough in hot weather and seemed happy with their life in 1-gallon pots.
They grew so much that I had to pot them up in a year-3 seedlings per 5-gallon
pot. Who knows how long that will hold them. They put on bulk much more
quickly than C. variabile but that was the only difference-both species were well
behaved and didn't complain.
I got still more ambitious and ordered more species of Crinum seed from
Silverhill. These arrived from Africa in mid- or late-winter. It was cold out so
I planted them up in small pots (sturdy 16 oz. plastic drinking cups) and set
them to germinate alongside Agave and Aloe seedlings; they were indoors and
under fluorescent lights. I just used cool white bulbs (40 W) and figured they
wouldn't need other wavelengths of light for 2 reasons: 1) as seedlings they
would likely only need blue light (not red), and 2) they were next to a big
window which got bright winter light.
The germinated OK, in fact some had germinated in transit and had pre-roots
when they arrived. Some of these pregerminators had been damaged, they had
bruises and spots where the tender growth had pushed against the packaging. I
soaked these seeds in Consan solution for a day or two-changing the double
strength solution twice daily. Consan won't hurt seedlings but it does a number on
fungi and bacteria in active growth-I reasoned that if the bruises had become
infected they would benefit from the Consan treatment and perhaps find time
to heal over the bruises. Also, after the Consan treatment I allowed the
pergerminators to dry for overnight at room temperature and then I dusted them
again with sulfur powder (they came in sulfur).
The point of all the drenching and dusting, etc., was to allow time for would
healing that might begin before I put the seeds in a high humidity atmosphere
for germination-I hoped that such treatment would nip any incipient
infections. In truth, the seeds did not appear to be infected when they arrived and
other than bruises were in very good shape.
Finally, I planted the seeds out in a mix that was about 50% humans and 50%
sand and perlite. The mostly all germinated and did fine-a few did not survive
but losses were below 20%--not bad for seeds coming all the way from Africa
in the wrong growing season.
In spring I put the seedlings outside-3-6 per 16 oz. cup. This is where
things started to go wrong. They adjusted to the sun OK because I used a shade
cloth. And they seemed to be getting along fine. Then June came along with
temperatures near 95 F (35 C) most days, and rain every day (30 days of
precipitation). I was busy in June and didn't pay attention; a number of seedlings
died (interestingly Eucomis vandermerwei seedlings didn't die but they stopped
growing). I lost seedlings of all types, even those reported to be from wet
conditions and which I supposed might grow like C. bulbispermum seedlings.
I probably lost 80% of the winter-arrived seedlings by mid-July and then I
took action. I carefully repotted them all in new soil mix, watered them with a
systemic fungicide, and gave them dilute fertilizer every 2-3 weeks. They
didn't really enjoy things until about mid-October when temperatures moderated a
bit. October was warm, but temperatures were often 10 degrees F cooler than
had been the case in July and August.
Tentative Conclusion: I think that some summer-growing South African bulbs
(including Eucomis vandermerwei) are not summer growers in Houston, TX. I
think they resent the temperatures (maybe the humidity too), and the respond by
going semi-dormant or even dying. Perhaps, if they were in the soil, with
cooler root temperatures, they might behave differently. But, in small pots the
soil stays at least 70-75 F all summer (night time temperatures) and the soil
may become much warmer in the day-even when the roots are shaded.
I think that these summer growers might turn out to be 2-season bulbs here in
Houston-at least while they are small. They remind me of roses the way they
pooped out in the hottest months only to pick up again in the fall. Some
Crinum are clearly not as happy here in Texas as is C. bulbispermum.
Cordially,
Conroe Joe