Bulbs from South America 2011

[Ezeiza]

One never stops learning. It is evident that Cape bulbs could not be grown in the UK yet yourself, David, Michael and Darren consistently produce scores of perfect specimens. The best growers can adjust their conditions until the plants look happy.

While one can theorically raise temperatures until the desired value, in our case (mild climate) there is no way we can provide cold conditions. Even in the fresher spot air is so hot that the plants have real difficulties for breathing. We can grow a number of cool/cold climate bulbs and perhaps even flower them ONCE but they gradually dwindle away. They use so much energy to cool down that there are no reserves to fatten the bulb. Our short chilly winter can give the false impression that it is similar to those in temperate Europe. While some days can be really chilly and a number of slight frosts occur, the warm season is lo long (now longer than ever before) and night temperatures so high that practically all temperate bulbs and plants succumb.

[PeterT]

The recently demolished alpine house at Kew addressed some of these problems with refrigerated benches, though I believe this aspect was not altogether successfull. Blowing air over water tanks and shading helps to keep a fresh atmosphere here, when heat is untimely for a plants growth cycle.
However I too find the greatest dificulty with plants from colder winters. The weather here is so erratic that mountain plants from very cold winter, continental climates cannot cope with untimely heat or cold. To grow them means combining a lot of tricks.
'The easiest trick' for these plants is to prevent freezing, thus removing the risk of untimely freeze and thaw. Along side this one has to manipulate the growth pattern to prevent growth too early in the year. This is often done by late planting and minimal watering.

 
I suspect that some South American plants may be used to a high altitude and tropical version of the British climate, also plants from the mountains in subtropical Africa. Some might adapt to the north Europaen climate? I suppose the difference is that in their homes these plants get a regular 24 hour  cycle of weather? whreas in the UK frost, heat, rain and drought may each be prolonged -even for months. so I expect that those which would adapt would be the exceptions.

Have there been any experiments with refrigerating tulip bulbs either while dormant, or when newly rooting prior to top growth? in order to maintain them in sub tropical climates?

[Ezeiza]

Of course refrigerated benches would solve most of the problems but costs involved are impossible to even think about it.

An alpine house in N. England (and Scotland?) where species tulips could be grown would suit most alpine Rhodophialas along with plants that are not bulbs like Alstroemerias. But, care must be taken as the bulbs may be tender and plunging pots is very important.

Yes, a lot of refrigerating bulbs experiments have been made mostly in Holland but that procedure is techncally a forcing or at least, this is how the plants react to it.

[PeterT]

Another grower of cold winter bulbs, in eastern Europe, with reliable frosts, told me of how he allows his beds of bulbs to freeze deeply then insulates them against thaw untill the last frosts are gone.

[Ezeiza]

I should have said that refrigerating the bulbs to later move them to our normal warm outdoors conditions is technically a forcing.

Freezing them and then exposing them to cool spring weather as in Europe is of course close to ideal.

[Rogan]

PeterT:
"Have there been any experiments with refrigerating tulip bulbs either while dormant, or when newly rooting prior to top growth? in order to maintain them in sub tropical climates?"

As far as I know Mary Sue Ittner of the Pacific Bulb Society does just this to keep her species Tulips in good health:
"Pictures below show bulbs that I have been growing in Northern California for more than twenty years, stored dry in summer, prechilled for six weeks in November, and planted in pots."

http://www.pacificbulbsociety.org/pbswiki/index.php/TulipaSpeciesThree#praestans

[Ezeiza]

Rogan, the standard procedure is to prechill them for 12 weeks but only in order to have the stems elongate properly, otherwise they flower practically at ground level. It does not substitute a chilly winter.

[Rafa]

Luc, I love your Alstroemeria!
here is blooming A. pallida and A. psittacina

[David Nicholson]

Very pretty Rafa.

[PeterT]

PeterT:
"Have there been any experiments with refrigerating tulip bulbs either while dormant, or when newly rooting prior to top growth? in order to maintain them in sub tropical climates?"

As far as I know Mary Sue Ittner of the Pacific Bulb Society does just this to keep her species Tulips in good health:
"Pictures below show bulbs that I have been growing in Northern California for more than twenty years, stored dry in summer, prechilled for six weeks in November, and planted in pots."

http://www.pacificbulbsociety.org/pbswiki/index.php/TulipaSpeciesThree#praestans

Thanks Rogan but my musings were really about finding a way of maintaining temperate bulbs in a tropical climate. As Alberto says the procedure Mary Sue Ittner is carying out would affect the flowering display but I expect her winters would be cool enough to grow the plants more naturally, and her summers not too long and hot/ humid to stress the bulbs stored dry and cool, or else in the ground.

Luc, I love your Alstroemeria!
here is blooming A. pallida and A. psittacina

Yes I agree Raffa, but yours are lovely too, as David says.

[Rogan]

"Thanks Rogan but my musings were really about finding a way of maintaining temperate bulbs in a tropical climate."

Well, what do you expect from someone who's never grown a Tulip in his life! Well, I do have 6 small seedlings...  which does make me an expert you know   

[PeterT]

I should be glad to know how they do, good luck with them

[Luc Gilgemyn]

Luc, I love your Alstroemeria!
here is blooming A. pallida and A. psittacina

Gorgeous Alstroemeria Rafa !! 

[bulborum]

Very nice ones Rafa

I just ordered seeds from:
Alstroemeria diluta ssp. chrysantha
Alstroemeria graminea
Alstroemeria hookeri
Alstroemeria kingii

are there special tricks
sowing months ?

Roland

[Paul Cumbleton]

Hi Roland,
Research at Wakehurst Place (Kew's other garden) has resulted in an improved method for breaking dormancy and achieving higher rates of germination for Alstroemeria. The method is:

Sow at high temperatures of 25 C daytime and min of 15 C night time and maintain these temperatures for at least 4 weeks.

Remove the seed and make a small chip out of each just above the embryo (which can be seen as a dark spot).

Re-sow the seeds and reduce the temperature to 10 C (which is the optimum, though germination will still occur at lower temperatures down to freezing point)

I'm afraid they did not say when to sow!

Paul