Answer: I found a similar flower sundial in a book called Sunflower Houses by Sharon Lovejoy, which has delightful suggestions for kids' gardens. Her clock consists of flowers planted in a circle. The flowers and their approximate bloom times are as follows: 2 a.m.: convolvulus; 3 a.m.: Egyptian waterlily and goatsbeard; 4 a.m.: spiderwort, flax; 5 a.m.: chicory; 6 a.m.: morning glory, day lily, iceland poppy, cape marigold; 7 a.m.: African marigold, madwort, St. Bernard lily, white water lily; 8 a.m.: scarlet pimpernel, fringed pinks; 9 a.m.: marigold, tulip, ice plant, pink sandwort, mallow, moss rose, and gazania; 10 a.m.: California poppy, golden star; 11 a.m.: Star-of-Bethlehem, passion flower, sweet pea; 12 noon: goatsbeard, wild daisy; 3 p.m.: Vesper iris; 4 p.m.: four-o'clock; 5 p.m.: evening primrose, jimson weed; 6 p.m.: honeysuckle, moonflower (takes couple of hours to fully open); 7 p.m.: evening campion, sweet white nicotiana; 8 p.m.: night-scented stock; 9 p.m.: sweet rocket, postage-stamp plant; 10 p.m. to midnight: night-blooming cereus.
I hope you can give this sundial garden a try, although you might have to go without sleeping to fully appreciate it!
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