Expert: Mike Mascio - 10/1/2006

Question
Hello, I live in Zone 5 (Denver Colorado) I have heard that morning glorys are annuals in my zone & yet I see the same houses in different areas of town have the same morning glorys every year. Do you know anything about them. I plan on planting them on the south side of my house, much warmer area. Thanks for any help you can give.  

Answer
Steve, morning glories are annuals and must be replanted every year. They will die immediately following the first frost of the autumn season.

Morning glories do self-sow, meaning that once the flower is spent and the plant forms the seed pod, the seeds fall and hibernate over the winter. They then germinate again the following spring. This may be why it seems your neighbors are growing the same variety every year. Or they may be like me and purchase the same seeds or seedlings every year. Once a gardener finds a variety they like, they will normally stick with it. In my case, I prefer the Heavenly Blue variety.

Since morning glories are fast growers, you can sow the seed immediately following your last expected frost next spring. They germinate quickly. In most areas of the country, they do not bloom until late August and continue to bloom through most of October. They require very little care, but I do advise amending the soil with organic matter such as compost or peat moss just before planting. Supplement the fertilization with a granular or water-soluble product high in phosphorus to promote blooming.

I hope this answered your question. Please write again if I can ever be of assistance.

Regards,

Mike