Sternbergia autumn 2012

[Gerry Webster]

........... and after four years of trying, without a single flower, I consigned mine to the compost bin at re-potting time.

David - I find this difficult to understand. In your part of the world they should not be a problem, at least under glass. Which species were you growing? In spite of what is sometimes said, I have found S. lutea (garden centre) more reliable than S. sicula - the latter varies according to clone. Having said that, one of my clones (from a John Marr coll.) which used to flower regularly no longer does so. Puzzling.

[Gerry Webster]

Sternbergia sp.

S.sicula or S.lutea subsp.sicula or S.lutea. Take your pick

A gift from a kind forumist. This fine form from Corfu seems more willing to flower in my frame bed than some others.

[David Nicholson]

David - I find this difficult to understand. In your part of the world they should not be a problem, at least under glass. Which species were you growing? In spite of what is sometimes said, I have found S. lutea (garden centre) more reliable than S. sicula - the latter varies according to clone. Having said that, one of my clones (from a John Marr coll.) which used to flower regularly no longer does so. Puzzling.

Gerry, I've had sicula under glass (sent to me by Anthony Darby in 2009) that never flowered and eventually wasted away and lutea in the garden in a number of plantings some of which rotted away whilst others made just a few squinny leaves. I think my Summers are just to wet for them.

[ashley]

Very nice Gerry
Like David, my experience has been disappointing and I am reluctantly inclined to write sternbergias off as 'too hard' under the cool, damp, overcast conditions that dominate our oceanic climate.  However at a talk here in Cork last week Paul Cutler, Head Gardener at Altamont Gardens (of snowdrop fame), showed sternbergias flowering abundantly in gravel at the base of a wall.  I understood this to be in his garden, presumably near Altamont SW of Dublin, therefore inland but not too different from my own conditions.  Yet again it shows how success with these plants depends on careful siting. 

[Gerry Webster]

My garden is about 2km from the sea & I think of it as being hot & dry. Although Sternbergias will survive & grow in the open garden they will not flower. So, all mine are under glass & even so the results are erratic - different clones vary in their willingness to flower, especially in a frame bed; results in pots are somewhat more consistent. Every year I'm surprised that Poul seems to get such good results in the open garden.

I can't make any kind of intelligent comment on Tony's suggestion that "they may only need a short burst of extreme heat to flower well" since I keep those I grow in pots as hot as possible for as long as possible & this seems to work (mostly). I suppose some degree of prolonged heat may kill the bulbs but, if so, I have yet to discover it.

[Gerry Webster]

Sternbergia enthusists may be interested in these herbarium specimens from the Berlin Botanic Garden.
Specimens of S. greuteriana from Karpathos can be found here. They show no signs of stolons & the shape of the tepals seems somewhat variable, from acute to obtuse.

http://ww2.bgbm.fu-berlin.de/

Enter the site & then enter the species name

[tonyg]

I can't make any kind of intelligent comment on Tony's suggestion that "they may only need a short burst of extreme heat to flower well" since I keep those I grow in pots as hot as possible for as long as possible & this seems to work (mostly). I suppose some degree of prolonged heat may kill the bulbs but, if so, I have yet to discover it.

I should have added that my sternbergias, several forms incl the JRMarr form, have in the past flowered well after cool wet summers here, but we usually get a burst of heat, as this year, even in a 'cool wet summer'.  Just an observation and a question as to what triggers flowering.

[Gerry Webster]

Sternbergia greuteriana

Or: S.lutea subsp. greuteriana or S.lutea. Take your pick.

A recent gift from Melvyn; a CITES approved  collection from Crete (Omalos). This form is tiny (c. 4cm tall) much smaller than a plant, probably from Karpathos (c.7-8cm tall), which I posted in Sept. 09 & which is not doing well this year:

http://www.srgc.net/forum/index.php?topic=2940.105

[pehe]

My garden is about 2km from the sea & I think of it as being hot & dry. Although Sternbergias will survive & grow in the open garden they will not flower. So, all mine are under glass & even so the results are erratic - different clones vary in their willingness to flower, especially in a frame bed; results in pots are somewhat more consistent. Every year I'm surprised that Poul seems to get such good results in the open garden.

I can't make any kind of intelligent comment on Tony's suggestion that "they may only need a short burst of extreme heat to flower well" since I keep those I grow in pots as hot as possible for as long as possible & this seems to work (mostly). I suppose some degree of prolonged heat may kill the bulbs but, if so, I have yet to discover it.

In hope that I can share my success with Sternbergia in the open garden with other forum members, is here a description of the climate and my Sternbergia site:

The climate in Denmark is coastal temperate.
Rain: 722mm/year (187mm June-august)
Average temperature: June-august 15.6 C, dec-feb 0.7 C
Max/min temperature: august 30 C/feb -18 C

My garden is 5 km from the sea. I grow most of my Sternbergias in front of a wall facing south-west, see the following photos.
The sites very close to the wall is most successful:
Lutea1: Many flowers every year. Flowerbuds are just visible now. Increases well.
Sicula Dodona Gold1: Many flowers every year. Flowering almost over now. Increases well.
Greuteriana: Many flowers every year. Flowering starts now. Increases well.
As an experiment I have planted Sternbergia candida this summer here, hoping for the best!
(Here I also grow Narcissus romieuxii, which flowers reliably in December if not to cold).
 About 0.5 m from the wall:
Lutea2 (same clone as  lutea1): Occasional flowers and much later than 1. Leaves have just poken through the ground and are not visible at the photo. Slow increasing.
Sicula Dodona Gold2: 1-3 flowers, about 2 weeks later than 1. 2 buds visible now. Very slow increase.

The soil is sandy loam with good drainage.
Feeding: Potassium sulphate once in oct/nov, tomato fertiliser 1-2 times during growth period.

I hope this can help others to success with this wonderful species.

Poul

[pehe]

Sternbergia enthusists may be interested in these herbarium specimens from the Berlin Botanic Garden.
Specimens of S. greuteriana from Karpathos can be found here. They show no signs of stolons & the shape of the tepals seems somewhat variable, from acute to obtuse.

http://ww2.bgbm.fu-berlin.de/

Enter the site & then enter the species name

Interesting site, Gerry! The Sternbergia greuteriana in my previous post is from Karphathos.

Poul

[Gerry Webster]

Poul - the details of your garden are very interesting. I see that your average summer temperature is quite low - lower than here - though you have a high in August. Maybe Tony is right & a short burst of heat is all that is required.  Perhaps your sandy soil helps? Does it get very dry? My soil is quite heavy & though I have added lots of grit it doesn't really dry out in summer.

[Tony Willis]

some sternbergias in flower today

general view
Stenbergia lutea Greece Kosmos
Sternbergia lutea Turkey Milas
Sternbergia sicula Selia Gorge Crete from Alan Edwards

[Melvyn Jope]

Nice plants Tony.

Sternbergia lutea from seed collected Kythera April 1997.
S. greuteriana from Omalos, one bulb having two flowers on one scape.

[krisderaeymaeker]

Thanks Poul ! Very interesting !
Very beautiful Gery ,Tony and Melvyn ! Much better then here with me .Under glas no flowers yet .In the rockgarden was lutea flowering today.
The flowers are 7 cm wide .

[pehe]

Poul - the details of your garden are very interesting. I see that your average summer temperature is quite low - lower than here - though you have a high in August. Maybe Tony is right & a short burst of heat is all that is required.  Perhaps your sandy soil helps? Does it get very dry? My soil is quite heavy & though I have added lots of grit it doesn't really dry out in summer.

Yes certainly my sandy soil is an advantage. It never gets too wet in the winter and dries out in the summer. During a 'normal' summer we have one or maybe two periods with low rain and then the soil gets very dry. But choosing the right clone is very important too. I have once tried a 'garden center' lutea close to the wall. In average it flowered every third year. Now I grow it under glass and it flowers reliable every year.

Poul