I have a soft spot for vines. I love their exuberance and the way they can cover something plain and turn it into something gloriously beautiful- the house I grew up in had an old wooden fence along the back of the yard that was covered with blue morning glories that my grandfather had planted years before I came along. Being southern California, they bloomed most of the year. They grew so thick- never got pruned or cut back- that when someone set fire to the fence, the ancient wood burned but the morning glory vines were thick enough and green enough to continue to hold themselves up and stand there, scorched but defiantly blooming. Morning glories are the fastest vines you can plant, and one of the prettiest. And they are dead easy to grow.
Morning glories come from the same large (at least 500 member) family as sweet potatoes. Some members of the family can be quite invasive, mostly in hot climates but some even up north. The ornamental morning glories, though cousins to field bindweed, are not invasive up here. They are strictly annuals in the inland northwest. Most of the ornamental morning glories are descendants of Ipomoea tricolor or I.purpurea, with a few I.imperialis thrown in. Their trumpet shaped flowers open in early morning and close around noon, but even in the afternoon the vines are handsome, with their rich green, heart shaped leaves. Except for some of the dwarf I.imperialis types, they need something to climb on and will cover things rapidly- a trellis, strings, porch railing, shrubs, slow moving pets. I grow most of mine on strings that go to the porch railings; come autumn, the vines die and I just cut the strings down and throw them away, vines and all. This year, I’m going to put out an old metal headboard and let some grow on that.
Morning glories are said to prefer full sun, but summer days are so long up here in the Spokane area that they work fine even if they aren’t on a southern exposure. Most of mine are on the east side of the house and they thrive there. Morning glories do best on a soil that isn’t overly fertile; grown on fertile soils they will be large, lush and green, but not very floriferous. They can grow in poor soils that many ornamental plants won’t tolerate.
Morning glory seeds are very hard. To speed their germination, you should either nick them with a file or knife, or give them a warm water soak: place them in a small container and pour hot (never boiling!) water over them and allow them to sit for 24 hours. If you wish to start them outdoors, do so in mid-May when danger of frost has passed, sowing them ½”deep. To start indoors in mid-April, remember that these are plants that seriously resent having their roots crowded. Either sow in 4” containers or, if you sow in smaller containers make sure you transplant them up a size any time the roots touch the walls of the containers. Keep an eye on them and don’t crowd them; they will start twining around each other and be a serious nuisance when you try to separate them at transplant time. You may have to put a bamboo stake or twig in the pot for them to climb if weather doesn’t permit you to transplant them out before they start twining. Germination takes about a week; less if they are given the hot water soak. Once you have grown morning glories in a spot you can usually count on them self seeding; the self seeded plants always seem to be more successful than the ones I start indoors. I have a patch of purple ones that return year after year to create a beautiful show, although last year’s wet spring and late summer set them back seriously.
The color range of morning glories covers the white/red/purple/blue range. ‘Pearly Gates’ is the usual white one; ‘Heavenly Blue’ the standard blue although these days there are darker blues available while ‘Blue Star’ is light blue with a dark star in the throat. There are various reds; ‘Scarlet O’Hara’, ‘Crimson Rambler’ and ‘Scarlet Star’ are all readily available. ‘Grandpa Ott’ and ‘Knowlian’s Black’ are both purple with red throats. ‘Chocolate’ has huge flowers of a brown-purple. There are types with variegated leaves, while ‘Flying Saucers’ and ‘Tie Dye’ both have blue and white streaked flowers. There are even pink ones, but I have never gotten them to grow well and bloom for me- I don’t know what I’m doing wrong with those!