I took cuttings from a geranium, a "Martha Washington" from the supermarket last fall. The cuttings soon produced leaves and survived the winter in a cool room with much light alongside the 'parent' plant.

Come spring the parent plant started to bloom profusely but the cuttings just sat there doing nothing. I took one up and found no roots. I took all the cuttings up and found no roots, just leaves on what appeared to be dead stems. Note, again, the conditions are the same as the parent plant which is now blooming profusely.

How do I get geraniums to root?