Commercial cultivation of Tuberose (Rajnigandha) in India

December 21, 2020 Agrovista

Commercial cultivation of Tuberose (Rajnigandha) in India

Tuberose (Polyanthus tuberose) is one of the most important bulbous ornamental plants, commonly known as Rajnigandha. It belongs to the family Amaryllidaceae and is a native of Mexico. It has long been characterized for its fragrance and milky white beauty. Blooms are mainly used for garland, bouquets, and cut flower trade. The waxy white flowering spikes of single, as well as double-flowered varieties with sweet fragrances, are in great demand for indoor decoration, particularly in metropolitan cities of India. Besides decoration, flowers of single varieties are used for oil extraction as they have more oil content than double ones.

In India, it is mainly grown in the regions of Kalaghat and Ranaghat near Calcutta in West Bengal on a commercial basis for flower spikes and perfume. However, there is tremendous potential for its commercial cultivation in north India.

Climate and Soil Requirements for Tuberose Cultivation

Climate: For its successful cultivation, it needs high humidity with an average temperature ranging from 20 to 30 °C, which is confined in coastal areas. Tuberose requires warm and humid weather conditions; for flowering, mild weather conditions are preferable. Tuberose grows well in sunny conditions; hence, the planting should be avoided under shady or semi-shady conditions.

Soil: Tuberose can be cultivated on various soils which range from sandy loams to clay loams under better agronomic practices it can be grown on soils on saline as

well as acidic soils. The soil must be well-drained and must have good aeration The pH range of the soil should be between 6 – 6.75.

Varieties of Tuberose ;

There are three types of tuberose:

single-flowered, semidouble, and Double-flowered.

Single flowered have only one row of petals, semidouble with two or three rows and double types more than three rows of petals.

Table of Contents

Varieties	Characteristics	Image
Single varieties
Calcutta Single	White flower variety. A single spike has a length of 60 cm, giving approximately 40 flowers. They are mainly used as loose or cut flowers
Prajwal	Released by IIHR (Indian Institute of Horticultural Research), Bangalore. The variety is developed with the crosses between “Mexican Single” and “Shrinagar.”. It contains slightly pink-colored flower buds from which white-colored flowers are born. They are mainly used as loose or cut flowers
Double varieties
Rajat Rekha	Released by NBRI (National Botanical Research Institute), Lucknow. Its flower contains silvery-white color streaks along the middle of the leaf blade.
Pearl double	Pearl double is given its name as it contains red-tinged flowers, which are known as pearls. They are used as cut flowers, loose flowers, and for essential oil extraction purposes.
Vaibhav	Released by IIHR (Indian Institute of Horticultural Research), Bangalore. The variety is made by the crosses between “Mexican Single” and “IIHR 2”. It contains greenish color flower buds from which white color flowers are born. They are used for cut flower purposes.
Other Varieties	Single; Arka Nirantra, Pune Single, Hyderabad Single, Khahikuchi Single, Shrinagar, Phule Rajani, Mexican Single. Semi- single; Kalyani Double, Suvasini. Double; Hyderabad Double, Calcutta Double.	Variegated; Swarna Rekha Variegated single; Rajat (having white margin) Varigated Double; Dhawal (having golden margin)

Planting Time of Tuberose;

Under North Indian climatic conditions, the blooming period is from May to December, with maximum intensity from July to September. Bulbs remain dormant from January to March.

Planting is done from April to July on the northern plains and May to June on the hills. However, March-April planting is preferred on moist soil in West Bengal.

Planting of tuberose ;

Bulbs are planted 25 to 30 cm apart in rows and 15 to 20 cm. within rows. A spacing of 50 to 60 cm should be kept between every fourth and fifth row to facilitate the plucking of flowers and other intercultural operations. Planting depth ranges from 3 to 6 cm depending upon the size of the bulbs; the bigger the bulb, the more depth. About 400 to 500 kg bulbs are required to plant one hectare.

Propagation of Tuberose

It is commercially multiplied by bulbs. A bulb size of 2.5 to 3 cm diameter is most suitable for better flowering. It can be propagated by seed, but seed setting is very erratic in single-flowered types, whereas it is not found in double-flowered varieties under north Indian conditions. Seeds are also difficult to germinate. However, it is useful for the evolution of new varieties.

Manuring in Tuberose;

A fertilizer mixture of nitrogen phosphorus, and potash in the ratio of 2:1:1 at 50 to 60 g/m2 should be applied as a basal dose at the time of planting This dose should be repeated at the time of flower stalk initiation. A foliar spray of urea and potassium sulfate in the ratio of 2:1 is quite beneficial. It should be sprayed @ 3-4 g in 10 liters of water after every 10 days interval. A mixture consisting of leaf mould, soil, and sand in the ratio of 2:1:1 to be used for pot culture

Micronutrients:
Apply a foliar spray of ZnSO4 0.5% + FeSO4 0.2% + Boric acid 0.1%.
Growth regulators:
Foliar application of GA3 at 50 to 100 ppm three times at 40, 55, and 60 days, respectively, after planting.

Insect pests and diseases of Tuberose

There is rarely an incidence of insect pests and diseases. However, aphid causes damage to the leaves and flowers, which can be controlled by a spray of Rogor or Malathion @ 0.2% Pre-sowing treatment of bulbs with Bavistin or Captan @ 0.2% should be followed to avoid fungal infection.

Harvesting and Yield of Tuberose

It takes about 80 to 90 days to produce flower stalks. It produces a flower stalk twice—once in July to October and another in February to March. With proper care and management, a good yield is obtained for two years from the same planting. Picking of the flower is done after the opening of one or two florets at the bottom. It may yield flower stalks of 4 to 5 lakhs (150-200 Q/ha) in the first year and 5 to 6 lakhs (200-250 Q/ha) in the second year.