Ipomoea purpurea, or the Common Morning Glory, is not a native of the UK but is grown here for its pretty purple flowers. This native of Mexico and Central America (Wikipedia) is normally treated as an annual when grown from seed, and happily climbs and entwines itself round anything near enough for it to get it tendrils around. It appears, if you have ever grown a plant indoors, that it can detect a nearby object and then grows towards it; however I am sure it simply launches itself outward, so that at some point it finds a frame, whatever shape or form that may take, to wrap its tendrils around. If the young seedlings grow near to each other they will entwine themselves around each other and thereby become very difficult to separate.
The leaves of the morning glory are heart shaped and the twining stems hairy, unlike its near relatives the field and hedge bindweed whose stems have very little or no hairs. Ipomea’s seeds are said to have psychedelic properties, and are classified as poisonous by seed merchants. Both Ipomea purpurea and Ipomea tricolor contain LSA, (Lysergic Acid Amide) presenting an experience said to be similar to LSD. Internet sources indicate that the seeds can be crushed, eaten or soaked and drunk, and will then provide an intoxication lasting 4to 8 hours. Evidently it was used by ‘Central American Indians in ceremonial and traditional ceremonies.’ Ipomea varieties also have a long history of use in Mexico where it grows in a manner similar to the bindweed here in the UK, rapidly covering anything near enough to get its tendrils around. A full and in depth investigation of Ipomea’s narcotic use can be found at; http://www.clusterbusters.com/lsa.htm
According to Scott Cunningham (Encyclopedia of Magical Herbs) the morning glory or bindweed (Ipomoea spp) are masculine plants, classified as being under the influence of the planet Saturn; the element water, and with powers over happiness and peace. Cunningham indicates that one can ‘Place the seeds beneath the pillow to stop all nightmares. And also that grown in the garden, blue morning glories bring peace and happiness. The root of the morning glory, according to Cunningham, may be used as a substitute for High John the Conqueror root.’ Not sure that I agree with him on some of these points although the pretty trumpet flowers are a joy to behold.
It is the Ipomea purga also called Ipomea Jalapa or Jalap Bindweed that he is known as High John the Conqueror root or the jalap bindweed This a native of South America, whose ‘tubers, varying in size from a walnut to an orange, are dark, umber-brown in colour, and much wrinkled.’ (Mrs Grieve) Cunningham places this variety under the planet Mars and allocates it the element water, used for success with 'money, love, happiness' and to bring 'success'.
According to Mrs Grieve ‘All the Convolvulus family have purgative properties.’ She goes onto explain that convolvulus scammonia (scammony) has a beneficial function as it ‘is used in homœopathy.’ However ‘there are three kinds of Convolvulus or Bindweed in our native flora.’ These she names as the ‘Field, Hedge, and the Sea Convolvulus.’ The Bindweed (field and hedge) is named as a common invasive plant here in the UK, however Mrs Grieve points to Anne Pratt’s very interesting observations; (Flowers and their Associations ) ‘while some twining plants follow the apparent course of the sun and turn round the supporting stems from left to right, others like the large White Bindweed or Convolvulus, twine contrary to the sun, from right to left, and never otherwise; even if the gardener turn it in another direction, the plant, if unable to disengage itself and assume its normal bias, will eventually perish.’ As a plant that lives truly in the hedge, neither in the woodland or in the field, it’s possible associations I find, appear rather intriguing. The field bindweed on the other hand, can grow along the ground, choking out crops and covering grassland.
It is also interesting to consider that ‘C. Batasas, the tuberous-rooted Bindweed,’ or sweet potato whose roots ‘abound in starch and sugar and produce a nourishing food.’ I have always found it amazing that within a genus of largely inedible plants there will be found one or two staple foods.