Common name: Hot Water Plant
Synonymous: Trevirana grandiflora
Achimenes grandiflora var. glabrescens
Achimenes grandiflora var. incisa
Achimenes grandiflora var. liebmannii
Achimenes grandiflora var. pubescens
Distribution ans habitat: Achimenes grandiflora is a subtropical rhizomatous perennial flowering plant native to Mexico and Central America, growing in mountainous regions from Chihuahua to Nicaragua.
It is cultivated as an ornamental plant because of its showy purple flowers.
Description: Achimenes grandiflora has hairy, upright, green or red stems 30-45cm (12-18 inch) tall. The leaves are hairy and rough, dark green on the upper surface and pale green or red underside. They are notable large – up to 15cm (6 inch) long and 8cm (3 inch) wide. Flowers appear on short flower stalk from the leaf axile, consist of a narrow tube flaring out into five broad lobes. They are deep reddish purple with a white throat and they can be up to 4cm (1.5 inch) long and 4cm (1.5 inch) wide. Each flower lasts for only a few days, but the flowering season is extensive: from summer to late autumn.
The roots are growing from a number of small rhizomes, each of which sends up a single stem that carries opposite pairs of heart-shaped leaves on short stalks. Achimenes grandiflora normally produces several such stems.
Houseplant care: For bushy growth, regularly pinch out the tips of young side shoots of the Achimenes grandiflora plant. It may also be necessary to provide some support to maintain the upright habit of this plant.
After the flowering season the leaves starts to shrivel. When they dry out, cut off the stems just above the surface of the potting mixture and put the dormant plant aside in its container until the following spring.
Light: An actively growing Achimenes grandiflora does best in bright light but should never be subject to the midday sun. During the long period of dormancy light is not a consideration. Bright light encourage the flowering.
Temperature: During the active growth period, Achimenes grandiflora plants thrive in temperatures ranging from about 15-26°C (59-79°F).
They tolerate temperatures as low as 13°C (55°F), but they cannot stand temperatures above 26°C (79°F). If high heat persists for more than a day or two, bulbs will turn brown and fail to open.
Rhizomes may be stored in any cool spot, but they will not survive frost.
Watering: Correct watering is especially important for the successful blooming of Achimenes grandiflora plants. As soon as the rhizomes start into growth in early spring, begin to water plentifully, as much as necessary to keep the potting mixture thoroughly moist. If the mixture is allowed to dry out even for a short period, the plant is likely to return to dormancy. Increase frequency of watering when plants are in flower, but limit the amounts; never let a flowering Achimenes grandiflora stand in water. After the flowering period, gradually reduce the quality and do not water at all during dormancy.
Avoid wetting the hairy leaf surface when watering the plant. Use warm or slightly hot water, never cold water.
Feeding: During the early weeks for the active growth period use a nitrogen-rich liquid fertiliser to encourage leafy growth. As buds form, change to a fertiliser that contains more phosphate and potash than nitrogen. Apply a one-eighth-straighten dose of fertiliser at every watering until the flowering period has ended.
Potting and repotting: Use an equal-parts mixture of peat moss, coarse sand or a substance such as perlite and vermiculite. To reduce acidity, add three or four table-spoons-fulls of dolomite lime, lime chips or crushed eggshells to four cups of mixture.
In early spring the clumps of newly spouting rhizomes should be carefully shaken out of the previous year’s potting mixture and, if desired, separated – they pull apart easily. Single rhizomes will soon form larger root system if placed horizontally about 1cm (0.4 inch) below the surface in a shallow pots of fresh mixture. Plant three or four rhizomes of Achimenes grandiflora in a 10cm (4 inch) pot. The mixture should not be packet down firmly, as this can cause waterlogging.
Gardening: Achimenes grandiflora, in subtropical regions can be cultivated outdoors. They are generally easy to grow as long as their basic requirements are met.
They have a winter dormancy and overwinter as scaly rhizomes, which should be kept dry until they sprout again in the spring. Some of the species and their hybrids are moderately hardy and can be grown outdoors year-round in zone 8, or even zone 7 with protection.
Stop watering altogether and allow the stems to die back naturally before cutting them back. Allow the rhizomes to dry out completely, then either store them in their pots or in dry peat or sand at a winter temperature of no less than 13°C(55°F). If stored over winter, plant them outdoor in beds or repot them in spring.
Position: Place Achimenes grandiflora in bright but indirect light. Avoid direct sunlight in the afternoon, but bright light will encourage the bud formation.
Soil: Achimenes grandiflora thrives in fertile well-drained loose soil. Any combination of leafmold, peatmoss, vermiculite and loam will work.
In early spring the clumps of newly spouting rhizomes should be carefully shaken out of the previous year’s potting mixture and, if desired, separated – they pull apart easily. Single rhizomes will soon form larger root system if placed horizontally about 1cm (0.4 inch) below the surface in a raised bed or a shallow pots of fresh potting mixture.
Irrigation: To start up Achimenes grandiflora in spring, water or immerse the pot in warm water. Thereafter water sparingly until signs of vigorous growth appear. Keep the soil or potting mixture moist at all times during the flowering season. Drizzle with warm or slightly hot water because cold water does upset the plant. Never over-watered Achimenes grandiflora since excessive moisture in the soil will kill the plant. Instead it appreciates the moisture in the air. Avoid wetting the hairy leaf surface.
Stop watering completely once flowering is finished to allow plants to prepare for winter dormancy.
Fertilising: Give to Achimenes grandiflora a montly liquid fertiliser from bud-formation until the flowers begin to die back.
Propagation: New plants are customarily grown from detached rhizomes, but an Achimenes grandiflora can be propagated from an 8cm (3 inch) tip cutting taken in early summer. A cutting will root easily in the recommended potting mixture if kept at normal room temperature in bright filtered light and watered plentifully.
Problems: Achimenes grandiflora is a trouble free plant if the care.
Give an occasional spray-mist with water to Achimenes grandiflora plants to prevent red spider mite infestation which is favourised by dry air.
Treatment: Spray with a suitable insecticide and raise the humidity by standing the pot on a saucer of moist pebbles.
Uses and display: Achimenes grandiflora can be used as houseplants, greenhouses or outdoor window displays or bedding plants.
As indoor plant, place Achimenes grandiflora on the window ledge or will make a pretty top table plant. Outdoors, these plants will look their best planted in a window box in a shaded position. Never less, Achimenes grandiflora will work planted in beds under a tree shade.
Foliage – green
Features – flowers
Shape – upright
Height: 64cm (25 inch)
Watering in active growth period – plentifully
Light – bight
Temperature in rest period – min 4°C max 13°C (-55°F)
Temperature in active growth period – min 16°C max 27°C (61-°F)
Humidity – low
Hardiness zone: 7-8