South American Plants – Petunia

Name – The name Petunia relates to any of a huge range of widely cultivated South American plants bearing funnel-shaped flowers in colours from white to purple. The names comes from the obsolete French pétun, tobacco, from Portuguese petum, a word that is in itself of Tupi-Guarani (native South American) origin.

Description - This tender annual must be one of the best known garden plants, with huge trumpet-like flowers in shades ranging from white through peach into pink, deep scarlet and deepest purple. A true blue and a real yellow remain elusive, but hybrids now exist that approximate those colours.

Origin – The Petunia is a member of the Solanaceae (or nightshade) family, making it the relative of some pretty dangerous plants such as deadly nightshade, angel’s trumpet and tobacco. One of the main historical problems of the petunia genus was that the flowers would die off or bruise, tear or otherwise damage very easily in rain or flood. New varieties show better and faster recovery after adverse weather but these are still flowers best planted in sunny situations – and avoid putting them anywhere that might drip on them! Traditionally, petunias are classified into one of two flowering types, either grandiflora or multiflora. Grandiflora types have large, heavily ruffled, individually ornate flowers which may be five inches in diameter. Multiflora types have smaller, less ornate flowers, but more of them – they are also thought to be more weather-tolerant. Given sun, this plant performs well in a wide range of soil types. Soil porosity is important to facilitate the development of a vigorous root system and to help prevent root rots. To test for porosity, dig a hole in your flower bed about a foot deep and fill it with water. The next day, fill the hole again and time to see how long it takes for the water to drain. If the water drains within eight hours, the porosity of your soil should be adequate for good growth. If the soil takes longer to drain, the incorporation of organic matter is recommended. Once established, petunias need little care during the growing season. Deadheading is not essential but it does give increased flower production in certain cultivars. If plants become excessively ‘leggy’ and stop blooming, cut them back to a few inches from their base to help rejuvenate the growth.

South American Petunia photograph by lil'bear, used under a creative commons attribution licence

 

© blueworldgardener.co.uk