Crocus October 2013

[tonyg]

Thanks Tony
would you recommend that Crocus tournefortii be planted in the open garden side in a sand bed or well drained clay soil to use the earth to wick away the excess moisture from fall rains?  or use a smaller pot?  This was in a 16 per flat size pot (~2/1/2"), i use 32s (~2" pot) for seedlings.

though we has a lot of rain and the pots in the sand plunge were quite damp, the undisturbed soil (clay) in the open garden is rather dry, but the disturbed garden soil is very wet.  I think the undisturbed soil texture is very important for drainage. but fall planted bulbs result in disturbed soil that absorbs too much water, then heaves in the winter freeze thaw cycles.
Rimmer

I, like Tony W, have had autumn rot, roots too.  Not for several years now though.  My problems came in years when I watered early and the weather stayed warm.  I think warm and wet is the starting point for this problem.  Now I delay watering pots until later, when the weather has cooled and the nights are a little longer.  Since this change, no rots.  In the garden soil you do not have the same issue with heating up.  Once cooled by rainfall the great mass of soil does not heat up so easily or so much as a pot. 
If you suffer such sever frost as to heave up the soil, I'd be planting Crocus in a sand bed.  I have had C tournefortii in a sand bed here for many years ..... but it does fine in light, sandy garden soil too.

[tonyg]

And finally Crocus tournefortii - or is it a hybrid?
Poul

How do we tell? 
It looks within the range of what I have grown as C tournefortii.  The only x boryi I grow is pure white but much more vigorous than any other boryi that I have grown, even increasing in the open garden like C tournefortii does.  It is the vigour that leads me to think it a hybrid ...... BUT seedlings have bred true so far, not any variation which I would expect from offspring of a hybrid.  The flowers do not completely close at night.  C tournefortii stay open, C boryi close.  Half way and maybe it is a hybrid.

[Rimmer de Vries]

I think warm and wet is the starting point for this problem.  Now I delay watering pots until later, when the weather has cooled and the nights are a little longer.  Since this change, no rots.  In the garden soil you do not have the same issue with heating up.  Once cooled by rainfall the great mass of soil does not heat up so easily or so much as a pot. 
If you suffer such sever frost as to heave up the soil, I'd be planting Crocus in a sand bed. 

THanks Tony
yes we get very severe frost here in Michigan- the ground is frozen for up to 3-4 months, and frost to depths up to of 2 feet or more in unprotected areas, is not uncommon. "Black Frost" - deep freezes with no snow cover is the norm.  Our frost line per the building code  is 42 inches, that is why i have the frames next to my house foundation to get the warmth of the house.

I don't think the cold bothers too many crocuses (if they dont heave or have roots exposed too long) , it just delays flowering to when it warms up.

I need more sunny sand beds!

Rimmer

[jens]

I, like Tony W, have had autumn rot, roots too.  Not for several years now though.  My problems came in years when I watered early and the weather stayed warm.  I think warm and wet is the starting point for this problem.  Now I delay watering pots until later, when the weather has cooled and the nights are a little longer.  Since this change, no rots.  In the garden soil you do not have the same issue with heating up.  Once cooled by rainfall the great mass of soil does not heat up so easily or so much as a pot. 
If you suffer such sever frost as to heave up the soil, I'd be planting Crocus in a sand bed.  I have had C tournefortii in a sand bed here for many years ..... but it does fine in light, sandy garden soil too.

Hi Tony I find Your explantion interesting. My experience also indicate very careful watering in the autum. I follow Ian Young's modus with the two storms. This year we have a very warm october in Denmark, which give my some thoughts about extra watering, at least to the specieces with leafs. I killed some bulbs over the past 10 years, not only Crocus but also Tulips, Colchicums and Fritillarias, where I blame my watering as the main reason, and not the Cold weather as many others forumistas.
Jens

[tonyg]

Hi Tony I find Your explantion interesting. My experience also indicate very careful watering in the autum. I follow Ian Young's modus with the two storms. This year we have a very warm october in Denmark, which give my some thoughts about extra watering, at least to the specieces with leafs. I killed some bulbs over the past 10 years, not only Crocus but also Tulips, Colchicums and Fritillarias, where I blame my watering as the main reason, and not the Cold weather as many others forumistas.
Jens

Yes, watering is critical in so many ways.  Always this is in combination with other factors.  Very free draining compost/soil (might be pure sand even) will allow excess water to quickly pass through - assuming pots do not stand in a puddle!  Extreme cold will be much more likely to cause harm when combined with wet conditions.   In a recent winter we had extreme low temperatures in early December.  Many of my potted bulbs were still quite wet after late autumn watering (like you I was concerned after a mild spell,) the complete freeze to -10C for over a week killed many bulbs that I had grown in the same site for ten or more years.  If I had not watered or if the freeze had come one month later perhaps the damage would have been less.

[jens]

My springflowering Crocuses gives no trouble at all, despite some Cold Winters in Denmark - they is grown in claypots. My loses is primarily amongst the autumnflowering. These years my autumflowering Crocuses is grown in plasticpots,, dug into a sandbed - about 5 - 7 cm. My focus with digging the pots down is to give the bulbs and roots some protection. Until now I'm more happy with this solution, but having trouble with some of the more tender autumspecies, eg. C. hyemalis, cambessedesi.
Jens

[Armin]

"Black Frost" - deep freezes with no snow cover is the norm.
I don't think the cold bothers too many crocuses (if they dont heave or have roots exposed too long) , it just delays flowering to when it warms up.
Rimmer

I agree if it stays constantly frosty. Fatal are situations when a warm weather period caused prematurely growth followed by days with deep black frost. So happend Feb. 2012. I've found almost all shots break off at the base by soil heave up due extreme temperature fluctuations (i.e. sunny day +12°C / clear nights -18°C). My raised beds with a moist sandy soil (w/o top protection) heaved up more compared to a heavy loam soil with sod (my meadow).
Armin

[fenius]

Great photos guys!!
Here's a few more of my I assume speciosus again?




I'm waiting for ligusticus to turn up but I'm afraid I lost them...this was last year's pic can you tell me if it was in fact ligusticus??

[Roma]

Crocus pulchellus albus in the garden 
Crocus ligusticus
Crocus banaticus
Crocus hadriaticus
Crocus kotschyanus leucopharynx

[udo]

Great photos guys!!
Here's a few more of my I assume speciosus again?
(Attachment Link)
(Attachment Link)


I'm waiting for ligusticus to turn up but I'm afraid I lost them...this was last year's pic can you tell me if it was in fact ligusticus??
(Attachment Link)
(Attachment Link)

Fenius,
the Crocus on your two second pictures is also speciosus.

[Janis Ruksans]

Hi Poul
this the my Crocus tournefortii from PC blooming a few weeks ago.

yesterday i noticed some shoots on Crocus tournefortii that seemed stalled in growth so gave a little pull and they dislodged as if the base was rotten.

is this problem due to too much moisture or inconsistent moisture after being covered and baked all summer?
We have had a lot of rain recently and these are in an open frame.

i have had this problem of stems aborting before with other fall crocus coming into bloom after heavy rain.

I suppose that this is some disease. I had similar in some years in few pots. If it would be overwatering - all corms would show same symptoms, but usually it is only 1-2 specimens in pot with 5 - 16 corms in each.
Janis (from waiting hall in Airport)

[Rafa]

just a couple of Crocus serotinus

[Janis Ruksans]

I agree if it stays constantly frosty. Fatal are situations when a warm weather period caused prematurely growth followed by days with deep black frost. So happend Feb. 2012. I've found almost all shots break off at the base by soil heave up due extreme temperature fluctuations (i.e. sunny day +12°C / clear nights -18°C). My raised beds with a moist sandy soil (w/o top protection) heaved up more compared to a heavy loam soil with sod (my meadow).
Armin

I have similar winter conditions and agree that it is most dangerous. But I start watering in first days of September and I'm doing it once a week up to frost starts. My substrate is very well drained. Now I started to change it (trying) - 3 parts of coarse sand and 1 part of peat moss + dolomite chalk and complex fertilizer. First two waterings - pure water after that 0,2 % fertilizer solution - NPK - 6-12-18+microelements. Crocus vallicola, autranii, suworovianus, banaticus get first watering in mid-August.
Janis

[Rimmer de Vries]

I suppose that this is some disease. I had similar in some years in few pots. If it would be overwatering - all corms would show same symptoms, but usually it is only 1-2 specimens in pot with 5 - 16 corms in each.
Janis (from waiting hall in Airport)

I unpotted the plants and yes 2 bulbs were soft and grayish, the other two were firm and had good root systems- the good bulbs are in the open ground in sand now.  All 4 bulbs are from 1 bulb i started with last fall from PC

Rimmer

[Gerry Webster]

Crocus tournefortii      

From an old Norman Hadden collection; Greece, Mykonos.