It pays to be optimistic
I am frequently asked about how long packets of seeds will last. Of course, since this is gardening, the answer is not simple. Whether an old packet of seeds will actually produce plants depends on a wide range of factors including the type of seed (tomatoes can last a decade but parsnips will not) how cool or warm they have been kept and whether the packet has been opened. But, at the end of the day, the best way to find out is to sow them! They won’t grow if you don’t sow them.
But I fell prey to ‘planting fear’ this spring with my acidantheras. I grew some in pots last year and kept them free of frost over winter. When I came to examine them this spring I had masses of cormlets, as expected, but the main corms, which replaced the ones I planted, were huge. They were not the conical shape I planted but massive and broad and flat, more like large-flowered gladioli.
Of course we are usually told to chuck the old acidanthera corms after flowering and I always understood that it was because they would not get the summer baking they need to form flowers. There is also the issue that the numerous cormlets will not flower the following year because they are so small and, unless dug and separated, they won’t reach flowering size. I don’t know why I thought the large corms would not grow or bloom but they were so wide and flat and I could not see a growing point. So I hesitated for months to plant them. It was stupid – what did I have to lose? It was, I am ashamed to say, July before I finally got tired of looking at the dry corms and planted them. I was only going to plant the large corms but, in the end, could not bear to discard the cormlets so they were al planted!
Of course, they responded by leaping into growth and, in the greenhouse, are now in bloom – what else? The pea-sized cormlets are leafy and growing well and the large corms have all produced flowers. What is odd, since the corms were so huge, is that the flower scapes only have two or three flowers. Is this typical of the large corms, or is it because of the late planting. I will have to try next year now I am more confident. I have never bothered to keep the corms after the first year because received wisdom is that they won’t flower again. Because I like them so much I am going to experiment more.
Not everything goes so well and my polianthes are bloomless after flowering last year. Of course they are very different creatures, related to agaves, and don’t really go dormant or form a true bulb or corm. I kept them just moist over winter and they have grown plenty of foliage this year but the basal sideshoots have not reached flowering size yet. I think I need to divide them and treat them better next year.
More optimism is needed for the next plant . In spring, among the cosmos I grew, there was one seedling with yellow foliage. The strain was ‘Purity Superior’ which I assumed was ‘Purity’ but without the annoying plants that don’t flower till November and think they are redwoods rather than cosmos. Anyway I planted my yellow-leaved cosmos in the beds with yellow and white plants and waited to see how it would do. It hated the dry, hot spell and I thought that perhaps it was too beautiful to live. But it has enjoyed the recent weather. There are now flower buds. Will the flowers be white? Will it set seed? Er, probably not. It is too late in the season to mature seeds. So I am going to have to lift it, pot it, keep it in the greenhouse and hope it is perennial. Some cosmos are perennial and there is a (small) chance I can keep this alive. Where cosmos flop and touch the ground they often produce roots so, if I can keep it alive, I may be able to take cuttings. If I can keep it, perhaps it will produce seeds next year. Lots of ifs. And will the flowers be white? If they are pink, will I be able to cope? Probably not!
Meanwhile, and again a sign of optimism, the mini-greenhouse, inside the greenhouse, is filled with cuttings. I can close the zipped door and the whole thing is a propagator at this time of year so no plastic lids are needed. So far everything is looking good and looks to be rooting. The main exception is the wallflower ‘Bloody Warrior’ which have a low rooting rate but that is because the cuttings were of rather tired, hard shoots because of the hot summer. I should have taken them in spring. I have a few rooted, which will help me sleep at night, and will take more in April.
The Biking Gardener 
That mini-glasshouse of cuttings looks so very successful – great plants for next year. Cosmos ‘Purity’ has thrown up purplish flowered plants here in a few years.
I have never had a pink flower on Purity but do get huge, late-flowering plants.
Your observations about Acedenthera are interesting because when I dug up my regular glads on Saturday several of them were HUGE and flat – I’ve not seen that before. I won’t hesitate to plant them next spring though!😁
It will be interesting to see how the spikes are on the ‘giant’ corms. I would have expected giant spikes on my giant corms but they are smaller than usual. But then how big will the corms be that have grown from the tiny cormlets I planted and will they bloom in year two?
Now we just have to wait nine months to find out…
One would hope that, with all the vast quantities of information available online nowadays, that some of it would be accurate. ‘Everyone’ seems to believe that Canna seed MUST be scarified and MUST be sown within a year. I know that such seed remains viable for many years and will eventually germinate without scarification. Scarification merely accelerates and synchronizes uniform germination. I really do not know how long such seed remains viable, but have found that any and all of such seed that I collected a decade ago in 2012 germinates very reliably once sown, without scarification.
Anyway, your big and wide Acidanthera corms are likely new corms. The old corms were the flat and shriveled discs that you might have peeled off from their undersides, or may have left attached if you did not notice them. They do not survive more than a year, but replace themselves with new corms above. I do not dig my Acidanthera corms annually, so they eventually work their way to the surface, like Watsonia and Crocosmia. I may dig them every several years or so to divide them, but only if I want to propagate more. So far, they do not seem to get too crowded to bloom.
Polianthes is a more difficult for us. I wish it wasn’t, since it is so popular. I want to grow the common ‘The Pearl’ because it is what I remember from the 1980s, but also find a cultivar with single white flowers to be very appealing. Anyway, I can not figure out what is lacking for it here.
Yes the big corms were the new ones. They were just so much bigger than the size I planted I was confused. The corms produce masses of tiny cormlets – at least 50 per corm. I would have expected polianthes to do well with you but, as you have said before, conditions vary a lot by location.
My first Montbretia did just the opposite. I brought very wide and flat corms from the coastal climate of Montara to the inland climate of Saratoga. On the coast, the foliage was VERY tall and wide, like huge gladiolus with small flowers. Inland, the big bulbs produced a bunch of small bulbs that generated much smaller and grassy foliage.
Polianthes used to be a more common cut flower crop near the coast here, which is why I thought that it would be happy in my garden, but like the Montbretia, it noticed how different the climate is.