'Host plants are highly conventional and behave like plants. But there are a number of rugged individualists whose behavior almost seems to have a brain or a will behind it-plants with personal timetables, plants with peculiar movements, queer feeding habits, and unplantlike reactions to certain stimuli. When it takes more than just a pretty flower to arouse the gardening impulse, perhaps some of these plants with personalities will do the trick.
The sensitive plant (Mimosa pudica) seldom fails to be provocative. Children love to poke it with their fingers to see it recoil at their touch and curl up its leaves in protest.
This may be grown as a winter house plant or in the summer garden.
Touch-me-not (Impatiens) is another plant that responds to finger-poking, but this time it is the ripe pod which is sensitive. At the touch of a finger it will burst and scatter a volley of seeds in all directions.
Obedient plant (Physostegia) has the reputation for extreme docility in permitting its blossoms to be pushed around to any side of the square-sided stem. There they remain until pushed again.
For a demonstration of pure wilfulness, on the other hand, nothing can beat some of the stem-climbing vines. Morning glories, bittersweet and Dutchman's pipe, for instance, choose to twine in a clockwise direction. Wisteria, honeysuckle and hops always go counter-clockwise. It is impossible to interfere with this instinct. Uncurl, if you will, the tip of any of them and wind it around its support in the opposite direction. Come back in a few hours and it will have reversed your work, stubbornly winding in its original direction.
Quaking grass (Briza maxima) is in almost perpetual motion because of the hair-thin wiry stems upon which its clustery little heads are borne. Children love it, and it is most attractive in flower arrangements, both fresh and dried.
Animated oats (Avena sterilis) is another plant with a movement all its own. When exposed to sudden moisture its spikelets twist and turn.
Telegraph plant (Desmodium motorium) is also a self- motorized plant. It has lateral leaflets which have a slow but constant motion up and down, similar to the signaling of a semaphore. This is a greenhouse plant which might take to a brief sojourn in the living room.
The gas plant (Dictamnus) is in a class by itself. On hot days it emits a gas which can be ignited with a match. The effect of a tiny flash of flame, or even a weak "pouf!", coming from a flower, is more than a little startling.
Scarlet pimpernel (Anagallis arvensis) is widely known
as the "poor man's weather-glass," because of its reputation as a forecaster of rain. When it closes up its blossoms in midday rain may be expected in about half an hour.