Crocus February - 2009

[Graeme Strachan]

Quote from: Graeme Strachan on February 28, 2009, 11:29:53 PM
Double Crocus
Last year I planted quite a few varieties of crocus in my lawn. I was intrigued when I found that quite a high proportion of E.P.Bowles were doubles. I researched this site and then the “rest” of the internet to find out more about this phenomenon. I found very little information

Fascinating - you may have a goldmine there   
It may be a result of storage conditions ie just a one-off seasonal occurrence.  If it is stable then you have a lucky find ... unless someone who knows the cultivars better than I do can report on this as a regular occurrence with E.P. Bowles. 

Crocus GOLDMINE I selected from open pollinated Crocus chrysanthus seedlings so exact parentage I don't know. It really at present is single more or less constant double (really semi-double) cultivar making ~80% of double flowers from large corms. Crocus tommasinianus Eric Smith is less constant and here it gives some 8 petalled plants only if left undisturbed for second year and well feed in previous season.
Willem van Eeden had another double chrysanthus, but less constant than Goldmine and he got from me few Goldmine corms for intercrossing but he never informed me about results and now I think he is too old. Pity.
Several other crocuses from time to time forms semidouble flowers. I got semidouble biflorus melantherus from John Fielding but stock still is too small to judge how constant this feature will be.
Janis

Tony – I’m “Bowled over” by your play on words. Stability of course is a major problem.

Janis – Thank you for your interesting reply. I note that no mention was made about the conditions required to “spark” a crocus into producing doubles. Can I infer that a double is a freak of nature and that its percentage success in success in future years is down to:-
1) Careful genetic selection.
2) Large corm selection.
3) Leaving undisturbed.
4) Feeding well the previous season.
5) A combination of some of the above

It appears to me that although the above are all important, there must be something missing to guarantee consistency
As “doubles”  are not too unusual, I am intrigued if anyone knows whether this is a modern phenomenon or if  this has been documented in the past.

However, with all this said, I am going to enjoy my EP Bowles doubles this season, give them a little TLC and see what happens next year.

          Graeme

[Maggi Young]

Well, Graeme, we shall be relying on you to follow up with your observations and report back in future years    . The fact that the flowers are what I would call "full" rather than very stuffed full doubles makes them very showy.

[hadacekf]

Some Crocus in my meadow produces on and off double flowers, but this characteristic is not steady. In the next year the flower is again normal.

[Graeme Strachan]

I did a quick count today and 29 out of 104 corms produced doubles. It will be interesting to see what happens next year.

Franz - What species of crocus are growing in your meadow and ones are producing doubles?

           Graeme

[hadacekf]

 Graeme,
The following species had doubles flower:
C. chrysanthus, goulimyi, and sieberi. There are seed plants
Pictures are on my website – Plants in my Garden- Unusual flower.

[Graeme Strachan]

Franz,
         Fascinating pictures of double flowers on your website. You have a marvelous garden. Bryce Canyon and Vernal Falls brought back many happy memories.

              Graeme

[Boyed]

Double Crocus

Last year I planted quite a few varieties of crocus in my lawn. I was intrigued when I found that quite a high proportion of E.P.Bowles were doubles. I researched this site and then the “rest” of the internet to find out more about this phenomenon. I found very little information

Graeme
I know the secret how to make your crocus produce semi-double or sometomes double flowers. If you treat your crocus corms to higher temperatures (around 25-30C) during summer rest period, next season most of them will produce semidouble blooms. For this effet, I usually place my corms on a sunny window seal and cover them with newspaper to protect from sun. That's it.

This method I usually apply to my tulip bulbs, the result is:
1. even smallest daughter bulbs produce flowers;
2. rate of propagation increases:
3. single varieties produce - semidouble blooms;
4. double, parrot and fringed tulips increas their intensity - heavy double, very scalloped and intensly fringed blooms.

[ian mcenery]

Double Crocus

Last year I planted quite a few varieties of crocus in my lawn. I was intrigued when I found that quite a high proportion of E.P.Bowles were doubles. I researched this site and then the “rest” of the internet to find out more about this phenomenon. I found very little information

Graeme
I know the secret how to make your crocus produce semi-double or sometomes double flowers. If you treat your crocus corms to higher temperatures (around 25-30C) during summer rest period, next season most of them will produce semidouble blooms. For this effet, I usually place my corms on a sunny window seal and cover them with newspaper to protect from sun. That's it.

This method I usually apply to my tulip bulbs, the result is:
1. even smallest daughter bulbs produce flowers;
2. rate of propagation increases:
3. single varieties produce - semidouble blooms;
4. double, parrot and fringed tulips increas their intensity - heavy double, very scalloped and intensly fringed blooms.

Zhirair very interesting. Are there any side affects to this process as far as the tulips are concerned?

[Boyed]

Ian,

On tulips it doesn't have any side effects. I would say that quite it positively reflects on tulips health. I forgot to mention, that in case of high temperature treatment most non-multiflowering tulips produce multiflowering stems, others bloom together with daughter bulbs formed next to the mother plant.

As to crocuses, I just consulted Janis and should say that I was not very accurate in my remarks. As you know some species doen't like dry storage, so this method would be effective mostly for those ones, which like dry summer baking. For example, Middle Asian species.

[Gerry Webster]

Graeme
I know the secret how to make your crocus produce semi-double or sometomes double flowers. If you treat your crocus corms to higher temperatures (around 25-30C) during summer rest period, next season most of them will produce semidouble blooms. For this effet, I usually place my corms on a sunny window seal and cover them with newspaper to protect from sun. That's it.

Zhirair - Interesting, but, given what we know about developmental biology, not surprising. It is well known that temperature shocks during development can produce  changes in the morphology of  both plants & animals. I would be interested to know what kinds of "doubles" are produced. Are they flowers in which the number of floral structures (eg, petals, stamens) has simply increased or, alternatively, flowers in which one kind of floral structure (eg, stamens) has transformed into another kind (eg, petals)?

[Thomas Huber]

Thomas can you name this Crocus ?chrysanthus? A gardening friend bought c100 'Advance' last autumn from a local garden centre. Not one is 'Advance'.

Did you forget the photo, Mark? Can't help you so far 

Graeme, I would like to see a photo of your double from the side, but from what I can see
this is 'Goldilocks' (not EP Bowles) which I've also seen often with double flowers.

[Boyed]

Gerry,
It is not a temperature shock. Many tulips originate from the areas with hot summers. So 25-30 C is a good and disirable temperture for them to perform well.
Number of petals usually increases from 6 to 8, sometimes 12. Sometimes one of six petals partially do the function of leaves coloured patially green (transforming into a leaf). Actually it doesn't reflect on stamens, but the cultivars having tendency to produce double stamens perform this feauture readily.

[Gerry Webster]

Gerry,
It is not a temperature shock. Many tulips originate from the areas with hot summers. So 25-30 C is a good and disirable temperture for them to perform well.

Zhirair - is this the soil temperature at the depth at which the bulbs grow?

[ashley]

I mean no disrespect, but why would anyone want double crocus or tulips
In my opinion their aesthetic value is entirely due to an elegant simplicity of form.  Whatever next - double junos

[Gerry Webster]

I mean no disrespect, but why would anyone want double crocus or tulips
In my opinion their aesthetic value is entirely due to an elegant simplicity of form.  Whatever next - double junos

Ashley - I  agree completely.