Using giberellic acid as an aid in germination
More species are germinating and because it’s still cold outside it’s a good time to ‘blag’ a bit about the germination. Each individual seed is a little wonder in itself: it does contain the plant we want – only if we can make it germinate! What I don’t like when growing from seed is not the ‘un-germination’ but the incertitude of what happened – what went wrong? – bad seeds, bad soil mix, too deep, too cold, too dry, not enough light, too much light… Also toooo much information on the web now can make things even more confusing. Here I’ll talk only about what I personally do.
Quite a few species (the most desirable) require ‘special treatments’ for germination like: stratification (moist & cold), alternation of cold and warm periods, incantations, sanding, soaking in GA3, frustrations… you get the idea. If you cannot easily provide a cold and moist period, the treatment with GA3 (acid giberellic) works in some cases wonders. I really like the convenience of GA3, which eliminates some variables from the process.
There is no need to seed way ahead of time or get buried under endless small pots that will get lost in the sway of other spring garden jobs. If the seeds are viable, they’ll germinate; if not, at least you’ll know it wasn’t your ‘brown’ finger at fault. Good to know, however, that GA3 at inappropriate concentrations can also destroy the seeds or lead to poor quality seedlings.
These are two methods I use:
1. Keep seeds in their package in the fridge (dry storage). When time to sow, prepare a GA3 solution 500-1000 ppm, soak seeds until next day, plant them in pots, cover with a thin layer of mix – place under lights (or outside if you sow late spring).
2. For the most recalcitrant – place the seeds into a moist paper towel inside a Ziploc bag, keep in the fridge (moist storage). When time to sow, squeeze the moist paper and add the GA3 solution over seeds, then keep until next day and then sow.
Germination should occur in 1-2(3) weeks.
Most excited about Thalictrums I am trying this year: T. delavayi – a Chinese meadow rue, with large lilac-mauve flowers (petal-like sepals; the one I bought a couple of years ago was really small and didn’t make it) and T. isopyroides with a really tiny, steel blue foliage that can grow in full sun – would be good for a rockery (from Turkey, Iran, Syria, Altai Mts.).
Note: Aquilegia also prefer/require light for germination so you should cover them with a very fine layer of potting mix (in case you forget about this they’ll still germinate but much slower).