|I started morning glories a couple of weeks ago and they are getting VERY tall! I still have about 6 weeks before I can set them outside. Can I pinch them back like sweet peas to promote side branching?|
|I don't pinch back sweet peas and I probably wouldn't pinch back the morning glory either. Young seedlings are pretty delicate and I try not to interfere with them too much. If you haven't encountered problems pinching back seedlings in this way you could try it...perhaps on only a few to see how it works out. If they still look OK in a week or two, you might try pinching the others--otherwise, the vines will be a tangled mess in 6 weeks. In any case, I would repot to a larger container as needed.
In the future, you may want to sow seed for morning glory a little closer to transplant time - perhaps 4-6 weeks prior to the last expected frost date. I am in the same general weather conditions as you are and I have a lot of success sowing morning glory seed outdoors, directly into the soil.