Curcuma roscoeana is one of the most difficult Curcuma to grow. The original tissue cultured clone seems to be sterile, but all of the newer imports are fertile. If you are trying to pollinate them, make sure its early in the morning. You really need to have thriving plants to propagate them yourself. They just don't make extra rhizomes, so the number of plants you have at the end of the season is the number of rhizomes you'll get.

Other than making sure you give them the best growing conditions, there is not much else you can do.

Tim Chapman

Thanks Tim. So how do the Thais do it? They must be getting them from somewhere. Are the newer imports also tissue cultured, just a more fertile clone? We just got some in, I'll wait and see if they turn out to be more fertile than previous ones. I had kind of given up trying when there seemed to be nothing going on with the flowers.

C. roscoeana was the first photo of a ginger I ever saw, some 30+ years ago. I fell madly in love, and vowed one day to find this plant. Well I found it, but it's still playing hard to get!

The thais have the distinct advantage of propagating a plant in its own natural climate. This species is common in northwest thailand. I don't know if they are tc'ing this at all, but they have started to do so with c. alismatifolia forms and new hybrids. Chances are your C. roscoeana are quite fertile. Have you successfully pollenated other curcuma? You will need to hand pollinate them. I get some seed set from bees on a few species, but the majority need some human help here.

There are some nice orange alternatives to C. roscoeana. Its beautiful, but just has too many negatives compared to Curcuma in general.

Tim Chapman

The only other orange one we have is the one they call Khmer curcuma-- do you know the species on that? That one has plenty of pollen, but I still have not been able to get any seed set. I've tried selfing it, going to another clone, and to another species-- nothing. I've successfully pollinated alismatifolia, gracillima (or is it rhabdota now?), thorelii, the one they call Maroon curcuma (again: species?), a few others, so I pretty much know the drill by now, it just seems to work a lot better on some than others.

I know it's a pain in the butt, but roscoeana's still my favorite, and people are always asking for it, so I'm going to keep trying.

-Lisa

Don't know the species of Khmer Orange, and there are some other forms that I'd bet are all the same species. Curcuma are very poorly known as there are several unid'ed things out there, and not many taxonomists working on them. those that are know that this is one confusing genus to work with!! C. gracillima and C. rhabdota are two valid species, however I don't think anyone is growing the real C. gracillima (it ain't much though anyway). C. rhabdota is what is being called candy cane and its other forms/names burnt burgundy, violet, zebra, chocolate zebra etc etc etc. Maroon Curcuma, have to see that for sure, but the ones i've seen labeled as maroon are usually forms of C. attenuata which is extremely variable.

There is a species similar to C. aurantiaca (not sure what it really is) that can have a lot of bright orange in it. It hybridizes and there are some good hybrids coming out with lots of orange and different colored tops. They of course are much easier to grow than C. roscoeana. If you've seen the thai curcuma book, there is a solid red hybrid in there that has major potential.. kinda has a roscoena/cordata like form. I finally have the red parent that was used and hope to recreate this beauty.

Most breeders are focusing on C. alismatifolia type crosses, fortunately there are some good people working on other types.

Tim Chapman

Tim Chapman

I have the thai book, the Maroon C. is on p. 74. Which is the red one you mentioned? There are several nice ones in there. I don't have aurantiaca yet, they're usually sold out by the time we get our order in, but that's definitely on my list, along with Sulee Rainbow, and some of the other hybrids I've seen on the web.

Speaking of which, there's a hybrid called Laddawan, which claims to be a cross between alismatifolia and cordata. Is that possible? I though they were in 2 different subgenera and assumed they couldn't be crossed. If I'm wrong, this would open up a whole new field to play in! The only successful hybrids I've made so far are between forms of a species (got some very nice offspring from Chocolate Zebra x Violet), but I'd really like to branch out if I can figure out how to get them to take.

-Lisa

not at home at the moment, so don't know the page numbers off hand. The red hybrid is towards the back.. I guess if you don't translate the thai you don't know its a hybrid, but it looks like a red cordata almost. Its a cordata cross with this unknown species, that took me several years to track down...by accident, a friend had it all along.

Laddawan (some people are labeling this ladderwan..arghh.) does appear to be alismatifolia x cordata. The one in the book IS NOT the same as whats for sale. The one on the market is actually nicer. Both forms were found in the wild. Some thai breeders have supposedly recreate the cross with different colors. It is a good plant to grow.

Sulee Rainbow is a friend's hybrid, and my introduction. Unfortunately there won't be many this year, but it and the next two Sulee crosses will be available next year barring any more set backs.

C. alismatifolia and C. rhabdota (either form) can produce some great hybrids, that would be a good one to practice on. Any of the blue flower types can cross with each other, or most at least. I'm sure there could be some other cross subgenera hybrids, but in general sticking within the subgenus is better.

Tim Chapman

Tim- I sent you an email. -Lisa

Last night a friend gave me a C. roscoeana. Without going to too much trouble, would you please give me a brief outline on the soil, light & temp requirements for this plant. Do any of this species have a scent? I think this species would be easy to get hooked on.