PBS Forum

Dear members living in the EU,
The spring seed and bulb exchange is now closed for orders. Please wait with any payments until you receive your order together with a payment slip from Martin.
The next EU exchange will take place in autumn and will be announced through all the channels. Please do not send any material to Martin in the meantime.
We wish you happy growing and a good summer!
Uli and Martin

Some information on my donation:
Amorphophallus linearis has long relatively thin rhizomes which should be planted vertically into deep pots. If the pot is not deep enough they will coil in the bottom or even try to push through the drainage holes which might damage the tuber. This species, like many others can be propagated by leaf cuttings, using not the entire leaf but only a segment of the finely divided leaf.

Dioscorea discolor: The tuber should be started as soon as possible with some bottom heat, otherwise it will take very long to sprout. It is fully dormant in winter and must be kept completely dry but the growing cycle goes well into late autumn/early winter. It is an easy plant and can be grown outdoors during warm weather, partial sun improves leaf coulours. A happy plant becomes quite big in one season, it is a climber which needs something to cling to.

Kohleria warczewiczii: splendid plant, colour combination is very special. Becomes big but can be kept to a managable size by re-starting it from cuttings. No dormancy, produces only very few rhizomes if at all. I sent in cuttings and would appreciate a feed back by those who received it. It is the first time I sent in cuttings and I would like to know if it works for you. This gesneriad is very easy to grow.

Sauromatum horsefieldii: I recommend growing it in a pot because the number of bulbils is enormous. It might become weedy in the right condition.

Spathantheum orbinyanum: large summer growing plant with attractive Acanthus like lush foliage, fully dry dormancy in winter. The flowers appear before the leaves and look like a small leaf on a long stalk. Only when you look under the "leaf! you will recognise a typical Aroid flower. Strange smell.

Following a question after my donation of Achimenes and other rhizomatous Gesneriads to the EU BX, here is how I get them through the winter.
In autumn I try to keep the vegetation going as long as possible after flowering. This ensures good and healthy rhizomes. I keep fertilizing with a general fertilizer rich in potassium to build up the scaly rhizomes. Once the plant goes dormant I stop watering immediately and move the pot into a room with about 12-15 degrees centigrade. The rhizomes remain in their pots in the substrate which should be completely dry. A trap to avoid is residual moisture in larger plastic pots which might lead to rot during dormancy. Overwintering the dormant pots in a cold but frost free greenhouse has led to almost total loss, it was too cold. Repotting takes place around this time of the year and the rhizomes are started with gentle bottom heat until shoots are visible. I do not store dormant rhizomes in bags: in paper bags they dry up too much and in plastic bags they might rot. Storage in the dry substrate has proven to be best.
The same procedure applies to Caladiom tubers, they are even more sensitive to too cold storage condition.
Attached is a picture of X Smithicodonia 'Heartland's Joy', a reliable hybrid

Well.... Maybe not as bright blue as I remember.... I checked this website https://flora-on.pt/#1Hyacinthoides+vicentina which is an excellent reference for Portuguese plants. I tried to copy a picture into this reply but it did not work.

Hmmmmm... Hyacinthoides vicentina grows not far from me on the Cape of St. Vincent, hence its name. This cape is the very south westerly end of Europe. I do not have a picture of the wild plant at hand. Does your picture show the color accurately? The typical form is bright blue and not almost white. And your plant seems to be somewhat too big and too lush but that might depend on the growing conditions. The wild population grows on pure sand. I agree that it is a very nice thing you have there.

Hello,

Welcome to the forum. As this forum is being used by an international community it would be great if you would specify where ,,here" is....... And it is also nice to know a name. You can set up an automatic signature like in this reply so that you do not need to do that in every individual post.
Your question is very good and once your locality is clear you should get a friendly reply. 

Bye for now 

Kohleria warczewiczii (sorry about the name...) in flower. The color combination is great. The plant is quite tall and does not produce many rhizomes and has no dormancy. Very easy from cuttings. I replace my plant regularly with new cuttings.

The website of Bulb'Argence is still active 
https://www.bulbargence.com/m_catalogue/

Lauw de Jager is the owner of the now defunct nursery Bulb'Argence in southern France. He sold a wide range of often unusual bulbs suitable for the Mediterranean Climate. He also wrote a nicely illustrated booklet on Mediterranean Bulbs but in French.
I also got the orange form of Moraea ochroleuca from him but it tends to disappear in my garden. It is planted in the open ground and I suspect mice........ there is just one single specimen flowering at this moment.
The yellow ones have also declined but seem to be less palatable to the critters.

Hello Arnold,

Does Tulipa altaica need winter chill or frost to stimulate flowering?

Hello Kelly,
Welcome to the forum! Don't worry about starting with a question, that's what this forum is for!
Your photos show Moraea ochroleuca, a South African Bulb. It may self seed a lot if happy but in my garden it is well behaved and flowers for quite a long time. There is also an orange form but it is not as common as the yellow form.
Bye for now

As we had good rains this winter the native flora on our land is particularly rich this spring. A lot of Serapias cordigera ssp. cordigera orchids are in flower now.

Dear Members living in the EU,
The second round of the EU Exchange will soon go online. The donation is still open but will close in due course, closure will be announced through the same channels. If you still have something to donate to your fellow gardeners, please get in touch with Martin directly to let him know. <garak@code-garak.de>
Once all the donations have arrived, Martin will put the list online and you will be informed through the same channels.
Please do not hesitate to get in touch with me if you have questions

Happy gardening
Uli

Hello @Bridget,
Can we put this topic on the agenda of the next board meeting? It may not be as straightforward as it seems at first glance and might need some discussion.
Hello @Ken,
The PBS encourages private contacts between members which can of course include private exchanges. The formal setup of a private exchange through the forum needs careful discussion as it might undermine the BX/SX. But it might also mobilize donations which otherwise would not happen.

Yesterday I came across this nice stand of the native Iris xiphium. Color is slightly variable, the plants are very elegant and graceful. They grow in acidic sandy soil among Cistus, Myrthus, Lavandula stoechas and other plants. Trees nearby are cork oak and pine trees.