Date: Fri, 14 Feb 97 13:46:05 MET From: Paul Temple 14-Feb-1997 1249 <temple_p@fangio.enet.dec.com> To: cp@opus.hpl.hp.com Message-Id: <aabcdefg599$foo@default> Subject: Re: Drosera planting times
+---------------------------+ TM From: Paul Temple
| | | | | | | | Dept: Digital
| d | i | g | i | t | a | l | Func: Net Comms
| | | | | | | | DTN: 7781-1582
+---------------------------+ Easynet: fangio::temple_p
Internet: temple_p@gmt.dec.com
Loc/MS: GMT
Christopher
>I have a book that tells me to plant non tuberous species in early
>spring, but doesn't say when to plant tuberous ones. The one tuberous type
>that I have is erythrorhiza. I also have some D.indica seeds, but my book
>doesn't mention this species - is it tuberous?
I hate books that tell you what to do but not why! (Have I invited trouble with
that statement?!) And I love describing "why's" so that the secrets don't
remain secret.
So, the reason why books recommend Spring for planting seeds is because of the
ambient heat and light levels. If a seed germinates, it is goiung to want heat,
light and water. Water must be provided artificially in most cases where seed
is to be cultivated. But most books assume seed growers are amateurs (no mails
on that please!) and that they might therefore be less likely to have access to
artificial heat and light (true, most amateurs don't use artificial
environments). Thus, as the seed needs strong light and reasonable warmth,
planting in autumn or winter would be a bad choice as light and heat are
relatively poor in those seasons (at least in the Northern Hemisphere). Then,
if you plant in summer, the logic is that you will have too little time to grow
the plant to sufficient size before autumn sets in, light and heat drops and the
plant begins to struggle, often growing too little (too cold) or too long (too
little light) - called etiolation - which weakens it.
Of course, if you have artificial heat and light, then you can plant seed
anytime. It makes no difference whatsoever, if you maintain your own controlled
environment.
As to when to plant tuberous species - my own view is that any time is fine and
recommendations to plant in Spring are poppycock (a quaint English word that
avoids the need for asterisks!). Tuberous sundews produce seed that are
notoriously difficult to germinate to a given schedule. Seed can easily take up
to two years or more to germinate. They will do so when the conditions suit
them, but I don't know anyone brave enough to have published exactly what these
conditions are for any species. In any case, Australia has a relatively harsh
climate. It is normal for seeds of plants from such climates, such as tuberous
species, to show a great variety in germination times as this maximises the
chance of some seeds germinating when conditions are better rather than worse.
So even if conditions are perfect, some seed of tuberous species may be
programmed not to germinate until a certain longer time has passed (in which
case they then await the next "perfect" time).
My best advise is to assume one rule is supreme over all others. For all seed,
including non-CPs, fresh seed always germinates beter than stored seed (except
where several periods of freezing - stratification - are required for
germination of some hardy species). So plant all seed as soon as you get it and
do you best to provide adequate light and heat as well as water. Never assume
ungerminated seed is dead unless you can see by the seed colour that it is.
Dead seeds turn dark brown or black usually. And dead seed rarely appear white
when cut in half), the seed is covered by mould, or the seed has been sown and
lying dormant for at least two years, ideally three. (Even the simplest of seed
can take time to germinate - I just had Pinguicula caerulea take about 9 months
to germinate where I expected it to take just 3 weeks!)
D. indica isn't tuberous but then there are many others who are far better at
describing all the CP species, so I won't embarass myself by saying more about
it, other than to say, sow seeds as soon as you can and you may need to provide
rather more heat than many other species require, simulating tropical conditions
(seeds often germinate at above 60 degrees F, maybe even above 70F) rather than
temperate (where above 50F is often adequate).
Regards
Paul
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:30:59 PST