How many saffron do you have Dirt Diver? Is lifting going to be a mish?
So far I've left mine in for 2 years before lifting, apart from one season where it was 12 months and a lot of work, so I went back to 2-yearly. They start to get crowded after a couple of years, and the flower production is supposed to drop, so if you want a reliable crop then you are up for some work. But hey, no different from planting/harvesting spuds really.
The corm doesnt get bigger and older: it grow a bunch of corms out of it. When they grow, little corms dissolve and make one or two new corms and these can give you the size increase within the growin season. A really big corm will make a cluster of about 5-8 new corms, some big and some smaller. I havent yet worked out exactly what to do to get lots of big corms, but the better the soil, the better the flowering, so maybe good soil makes large corms makes flowers?
The cool thing about how they grow, with the parent corm dissolving, is that when the leaves have been up about 6 weeks, you can carefully count the individual tufts of leaves where the corm was planted, and this will tell you how many corms that one has become. So say you plant 20 corms, within 4 weeks of coming up they flower and within about 6 weeks you know your 20 corms are now 53 corms. I just love that kind of instant reward!
The flower harvest depends on how well they were grown
the year before. So after you've had your early reward, any watering/weeding/fertilizing you do sets the corms up for the following autumn. It is worth keeping this in mind if you get tempted to let the saffron look after itself and disappear in a sea of weeds. The whole regime is quite the opposite to most vegetable gardening where you prepare the soil, weed etc and then get the crop.
I know saffron traditionally grows in poor soil on the side of field, in some pretty inhospitable countries (hot in summer, strong winds) but having got good crops in a vegetable garden bed I now wonder if the traditional approach is because saffron is the only thing that could be grown in poor soil and still get some kind of a yield. The better soil or fields are used to grow food for the families!
=Pip