Every year we take about 1,000 cuttings and I do have some observations:
(1) there is an ideal size for a tuber cutting and for us it is about 4 to 5 inches. Yes, we all have taken small cuttings as we have knocked them off of the tubers by accident. When that happens, I insert it into the same pot(no oasis wedges here) as the longer one and if it roots I will give it it's own pot later. Very small cuttings can take weeks longer to grow to the same size as the 4-5 inch ideal cuttings.
(2) fat cuttings often have hollow stems and do not root or take forever to root.
(3) I root cuttings in plastic bags under either fluorescent or LED lights. During the 12 or so days that I leave the cuttings in the bags , the ones that are grown with more light will actually grow a couple of inches taller in the 12 days. It seems that they are growing both leaves and roots and use the light to make energy to do so. My fluorescents are old and a bit dim but they do have enough light to get cuttings to root. The LEDs are putting out about 33% more light although I do need to check that guestimate .
(4) Leaf cuttings that for me are leaf node cuttings split into two pieces, are easy to root but take longer to grow. They need a couple of weeks more to catch up with tuber cuttings.
(5) Steve Lamb in his dahlia talk demo on Feb 28th explained how to take cuttings from plants grown to a large size and that was the method used by Kevin Larkin of Corralitos Gardens. If you want to make hundreds of cuttings of the same variety, it is the way to go and an advantage is that the plant when sliced and diced produces cuttings that are all of the same age and can be in the same flat. One of the more difficult things to control when shipping cuttings is putting together an order of several different varieties.
(6) I would like to trade some UNROOTED cutting with some of you growers. The success rate for them can be very high and the mailing cost very low. I will have extra cuttings to trade in a few weeks from now.
