Poinsettia Grown From Cutting
Last Christmas we were given a Poinsettia, which lasted well into the spring before starting to deteriorate. I took a cutting from it, dipped the cutting in hormone rooting gel and potted it up with a small clear poly bag over the top to give it a "mini greenhouse". I followed all the advice that I found on the web, watering sparingly etc. The plant lived on the kitchen windowsil, behind vertical blinds. It had plenty of daylight, but not direct sunlight. As it grew and developed more leaves, I took away the poly bag, leaving the plant open to the room air.
It grew from the original cutting, about an inch and a half tall into what it is now, four months later, about three and a half inches tall with ten well formed, rich green leaves.
However, over the last week the leaves have started to go yellow at the tips and outer edges and have curled a little. I suspect that they have suffered from the cold spell that we had and I have moved them closer to a radiator where they still get plenty of daylight.
Could it have been cold that upset the plant? - (we both work and the central heating is set to 16 degrees C during the night and whilst we are out at work).
Have I done everything correctly in propagating this plant from a cutting?
I read somewhere on the RHS site that plants should be fed about once a month with a nitrogen free fertiliser rich in potassium. Is that only for mature plants, or should I have fed my plant in this way?