Overwintering Diascia

Does anyone have any experience of overwintering Diascia (and Nemesia). Although most people grow it as an annual, it is a tender perennial. But mine seem to die at this time of the year anyway. Is it one of those long flowering plants that can just flower itself to death? Or am I missing a trick somewhere?

 

I had a salmon pink one that gave up and died, due to cold and wet I think. I still have a purple one that is as tough as old boots and has put up with very hard frosts.
Probably free draining soil helps, it's in a raisd bed.
Cover with a bit of fleece maybe?

 

I've just been googling about it, as I've never had diascia - but now I definitely will. Seems they're like penstemon - not guaranteed to make it through a hard winter, and it's recommended you take cuttings...

http://www.bbc.co.uk/gardening/plants/plantprofile_diascia.shtml
I have nemesia, and never thought about it much - but on checking I see it's half-hardy, and should be over-wintered in a greeenhouse..... hope that helps, Peter.

 

Thanks to you both - thats a good site. I should have mentioned that the plants were in pots that have been and will be kept frost free over winter. Even so some plants have already died. Dendo its a delightful plant, well worth having. Last year in the summer I took cuttings, that rooted so easily - you don't even need a lower node. And its very long flowering.

 

I have had diascias in pots outside for several years. Some varieties are hardier than others - the one that i have is something like Salmon Queen. Each spring i just rip it apart because it has taken over half of the pot and transplant what i need. Needs a good cutting back cause otherwise it gets a bit leggy.
I am wondering whether to buy some seed of the new seed raised varieties that are supposed to be compact.

 

Hi Geoff. I grew some from seed this year, and also got some as individual plugs. The plugs only cost about 60p each, and you can get a range of colours. There didn't seem to be any difference in final size (all perhaps 8 ins high). I have also has Nemesia, which is pretty similar, but they don't seem to be so robust. I put some in a pot with Diascia and the Diascia crowded the Nemesia out.

 

I have tried both, left them outdoors, and have had success and failure in different years. No idea why, I have a hunch that it is wetness rather than cold that does them in. I'd say that three years in four they get hammered, and such as come back are not worth the candle (even though they grow like stink), but once or twice I've had to thin them out and contain the next years growth.

 

Thanks Jazid. You have a point there about not worth a candle. There are many plants such as Petunias, Salvia Splendens, Salvia Farinacea, which are tender perennials, but everyone grows as annuals. I am never sure if this is because of the difficulty of overwintering them or is because the ones that do overwinter don't flower very well the next year.

I think you are right about the wet. Also some tender perennials (I don't know which and how many) go dormant in the summer heat in their native environment, which means they expect to be very dry during dormancy.