Annuals

Introduction

Annuals are an important group of flowering plants widely used for garden decoration, cut flowers and pot plants. Few types, however, are grown for attractive foliage. They have large number of species and many varieties which not only show variations in height and growth habit but also in the shape, size and colour of flowers. Annuals are very easy to grow, flower profusely in a short time in numerous shades of colour. Due to variation in the season of growth and flowering, several species grow well in summer and rains, while the majority of annuals are cultivated in the winter months in the plains.

Site and Layout

Most of the annuals require full sun, shade for few hours in the morning or midday adversely affects growth and flowering; western sun, however, is less important. The annuals are grown in mixed border or only one variety in a small bed. A strip of green grass in front of mixed border or between two beds improve the display of colour. It should be sufficiently wide for the use of lawn mower. The space for a mixed border should be large and of informal design. Plants varying in height and colour are planted in groups, tall plants at the back and shorter one gradually towards the front. Tall plants of Hollyhock, seedling Dahlia, Lady’s lace should go at the back; plants of intermediate height, e.g., Antirrhinum, Cornflower, Salvia, Larkspur are grown in the next group; the third clumps may consists of Dianthus, Aster, Wall flower, Anchusa, Calendula and Allysum Phlox, Pansy, Brachycome should be selected for the front patches. In small bed, usually one type of annual of attractive colour is grown. Salvia, Antirrhinum, Dianthus, Aster, Phlox are selected depending on the size and position of the bed.

Loamy and porous soil rich in organic matter is good for the growth and flowering of annuals. If the soil is clayey, addition of time in the rainy season will be useful to break the stiff soil and use of adequate organic manure will make the soil porous. Where the soil is sandy add clay if possible, for one cannot depend entirely on manure to improve the texture of the soil.

It is more artistic to allow the front annuals to fall over on the grass edge than to keep them in a straight line. To stiffen a wide herbaceous border, it is advisable to plant flowering and foliage shrubs which will act as a foil to the annuals and provide at the same time colour when the annuals are small or the beds empty.

Sowing of Seeds

Seeds of annuals are sown in bed or shallow seed pan. The seed compost should consist of 1 part each of garden soil and finely screened dry leafmould. The compost should be slightly moist before sowing, otherwise the water will not soak readily and the seeds will float on water. Sow the seeds thinly and cover with a fine layer of screened leafmould. Protect the seed pan or the bed from rains after the seeds have been sown. When the seedlings start sprouting, exposure to sunlight should be gradually increased, so that before transplanting they become sufficiently strong to bear the full-day sun. The seedlings are severly damaged by fungul disease under conditions of high humidity and cloudy weather and it can be effectively controlled by the application of fungicide. Most of the seedlings become ready for transplanting at four-leaved stage. To see the beds of annuals in bloom in late December or early January, sow the seeds in September and transplant the seedlings in October. For a display of colour in early February, sowing should be done in early October. Double and large flowering Petunia, Cineraria, Carnation and Stock, which require about 5 months to come flower, should be sown earlier.

Preparation of Beds and Transplanting of Seedlings

The beds should be thoroughly dug at least 30-40 cm deep as the rain ceases and the soil is dry. The clods should be broken, soil pulverised and dug again to make the soil of uniform tilth throughout the depth of the cultivated layer. Well-rotted cow manure should be mixed at the time of preparation of the soil. It is gently pressed to keep the seedlings from the seed bed or pan, care should be taken to minimise the damages of roots. Seedlings will establish in the ground in about a week, if light watering is done when necessary.

Watering

After the seedlings have started new growth, they are watered profusely, weeds removed from these beds when it is just moist and the soil is allowed to dry before it is again flooded.

Manuring

Organic matter not only supplies nutrient to the soil but also greatly improves its physical condition. Cow manure is the best and easily available organic manure. Fresh or half-rotted manure should never be used just before planting of seedlings. Chemical fertilizers should be used in very small dose. Mixture of chemical fertilizers and organic manure in the form of solution, if applied in low concentration during the vegetative phase of the plants will greatly improve the growth and also the quality and quantity of flowers. Fertilizers can also be used on the soil as dry powder followed by flooding.

Types of annuals:

There are various types of annuals.

  1. Early Blooming Annuals

  2. Ageratum, Alyssum, Balsam, Browalia, Candytuft, Celosia, Dianthus, Gomphrena, Marigold, Salvia, Sunflower and Zinnia are some of the early blooming annuals.

  3. Shade Tolerant Annuals

  4. No annual can thrive in full shade, but where light is dappled and filters through a light tree the following will thrive. It must be remembered that the quality and quantity of bloom will necessarily be poorer.

    Ageratum, Alyssum, Begonia, Calceolaria, Calendula, Candytuft, Cineraria, Clarkia, Dahila, Delphinium, Godetia, Impatiens, Larkspur, Lobelia, Lupin, Myosotis, Nicotiana, Pansy, Phlox, Salvia, Verbena and Vinca are the shade tolerant annuals.

  5. Annuals for Rockery

A rock garden in sun may not be entirely composed of cacti and succulents and patches of colour will brighten it. In a rock garden hardy types of dwarf annuals which thrive and flower in poor soil are usually selected. Ageratum, Alyssum, Arctotis, Brachycome, Nasturtium, Phlox, Portulaca, Verbena are some annuals suitable for this purpose.

Varieties

  1. Ageratum conyzoides (A mexicanum) (Compositae) Ageratum

  2. Popular annual flowering plant for beds and pots. The height varies from 15-40 cm depending on the variety. It develops into well-shaped plant with dark green foliage and the dwarf varieties are compact and widely grown for edging and in a mixed border. Blue or its shades like azure blue, dark blue are normally selected for gardens; salmon, pink and white are not so popular. In the plains, seeds are sown from September to November and the plants flower in 2-3 months after sowing. Pinching of taller varieties is done to make the plants bushy. Removal of faded flowers promoted flowering for a longer period.

  3. Adthaea Rosea (Malvaceae) Hollyhock

  4. It is a popular flowering plant throughout the world and commonly known as hollyhock. In tropical climate, hollyhock is treated as an annual, while in the hills it is grown as a perennial. The height of the plant varies from 1.0 to 2.5 m. large flowers 8-12 cm across appear on long erect stem at the axils of the leaves. It is mainly used at the back of the mixed border or along a wall. Plants of shorter height also make good pot plants. The flowers open successively from below towards the tip of the spike and continues to bloom for a long time till the temperature rises high, when almost all other annuals dry up. A wide range of flower colour is recorded in hollyhock eg. White, cream, yellow, rose, lilac, purple, scarlet and crimson. The flowers may be single, double and semi-double. The plants grow better when directly sown in site and extra seedlings are removed to maintain a distance of 50-60 cm. Seeds should be sown in September-October to get bloom during January to April.

  5. Amaranthus Caudatus (Amaranthaceae) Love-Lies-Bleeding

  6. This species is commonly grown to pots or in beds as a flowering annual during winter months and produces long pendulous plume like or headed spike, purplish crimson, light green and white in colour. The plants are quick growing and make a good display in groups in mixed border. The flower spike lasts for many days.

  7. Amaranthus hybrida (Princess Feather)

  8. It is about 1 m in height and bears erect crimson red plume like spikes. Its cultivation is similar to that of A.caudatus. A.tricolor splendens is one of brightest foliage plant, about 50-90 cm in height. The leaves are deep scarlet marked with patches of yellow or bronze green. A.tricolor rubra has bright red leaves. The seeds are sown in February and March and seedlings grow into a well-shaped plant in about 2 months and continues to thrive a during the summer plant in about 2 months and continues to thrive during the summer and early rains. It grows well in pots and can be effectively displayed as foliage plants during the season.

  9. Antirrhinum Majus (Scrophulariaceae) Snapdragon

  10. Antirrhinum is one of the most popular annual grown in garden. The plants have dark green narrow leaves, bear tubular flower with spreading irregular lobes on long erect spikes at the end of main stem and branches. According to the height of the plant, antirrhinum is divided into 4 groups-tall (80-120 cm), intermediate (55-75 cm), dwarf (25-50 cm) and miniature (15-20 cm). There are varieties with ruffled or double flowers.

    Tall varieties with long spikes are very attractive at the background of a mixed border. The cut flowers are very showy and last long. Intermediate varieties in one or mixed colour are useful for planting in small beds or in patches in mixed border and as pot plants. Dwarf varieties have compact appearance and produces large number of smaller spikes at the tip of the branches. These varieties are commonly grown in beds, rock gardens, pots and window boxes. Seeds are sown during September to November. The soil should be porous but rich in organic matter and nutrients. In antirrhinum there is a wide range of colour except blue and with one or more colours of attractive shade.

    Tetra or tetraploid varieties with larger flowers and double flowered varieties are spectacular improvement in the recent years. Those plants have large funnel-shaped flowers, lobes widely open, slightly ruffled at the edges. F1 hybrids or antirrhinum are vigorous plants and show better flowering than the common varieties.

  11. Arctotis Grandis (Compositae) African Daisy

  12. The species is commonly grown in the gardens of northern India. It grows best in porous soil, prolonged low temperature and less humidity. An appreciable improvement has been made in this species and the hybrids show wider range of colour and larger flowers. Normally A.gradis attains a height of 50-80 cms and bears white daisy like flowers with lilac centre. Large flowered hybrids, developed as a result of crosses between the species and hybrids, show various attractive colours like organge. Arctotis is very useful for bedding and rock gardens and also as pot plants. The seeds are sown in September-October in the plains and in March-April in the hills. Flowers appear in about 4 months from sowing.

  13. Calendula Officinalis (Compositae) Pot Marigold

  14. Calendula is a popular annual in Indian gardens grown in beds and pots. The plant has a dwarf, rosette growth, bears flower heads 6-10 cm in diameter on stout stalk, 20-30 cm in length. Large double flowers are attractive, singles and semi-doubles bear large number of blooms, in various shades of yellow and orange. The plants grow well in rich porous but moist soil and flower in 2 1/2-3 months.

  15. Callistephus Chinensis (Compositae) China Aster

  16. Aster is one of the most popular flowering plants throughout the world. In the plains only annual types are grown, but many species of perennial asters are cultivated in temperature countries. They are grown extensively in beds for the attractive flowers of various shapes and colour. Cut asters last long and are used in vases and floral decoration. Height of the plants varies from 15 to 60 cm depending on the type and variety. There are various types e.g., Giant of California, Ostrichplume, Commet, varying in the shape of the head and size, shape and arrangements of the florets. Wide range of colours include white, pink, rose, blue,scarlet,crimson,mauve, purple etc. Aster grows well in porous soil rich in organic matter in full sun. In the plains the seeds are usually sown in September-October, sowing in July-August is also possible in low rainfall area and plants bloom after 3 1/2 to 5 months depending on type, variety and climate.

  17. Celosia Plumosa (Amaranthacea) Cockscomb

  18. Cockscomb is a hardy annual and can be grown in winter, summer and rainy season.C.plumosa produces long silky feathery flower spike in various colours like red, orange scarlet, yellow and white. The height varies considerably from 80 cm in the tall ones to 25 cm in the dwarf varieties and intermediate ones having medium height in between.

    The feathery varieties with attractive shining spikes makes a good display in a mixed border. Dwarf types are good pot plants. The variety Cristata (C.plumosa var.cristata) produces orested flower heads, resembling the comb of cock in various colours like red, rose,organe,scarlet,bright scarlet,white,yellow,golden yellow etc. The height varies from 15 cm to 90 cm depending on the varieties.

    The seeds are sown in January-February, May-June and September-October for flowering in the summer, rains and winter respectively. Seedlings are transplanted at 4-6 leaves stage. Flowers appear in 2 1/2 to 3 months after transplanting.

  19. Centaurea Cyanus, Cornflower

  20. The plants are tall attaining a height up to 1 meter and are commonly grown at the back of mixed border. As the flowers last long, they are also used as cut flowers. Cornflower is a hardy winter annual in the plains and seeds are sown in September-October, flowers are produced in 3 to 31/2 months. There are varieties with pink, rose, maroon, purple, blue and white, mostly singly; double flowered varieties are also grown.

  21. Chrysanthemum (Compositae) Annual Chrysanthemum

  22. Annual chrysanthemums comprise of three species, Chrysanthemum segetum (Corn Marigold), C.coronarium (Crown Daisy) and C.carinatum. Corn marigold grows about 40 to 60 cm high and bears flowers 5.0 cm across in shades of white and yellow. Double flowered varieties are also available in this type.

    The crown daisy in much branched plants with finely cut foliage reaching a height up to 1 meter, size of the flowers varies from 2.5 to 4 cm and colour is usually in shade of yellow and white. Both single and double flowered varieties are found, but single is common.

    The tricoloured chrysanthemum (C.carinatum) are the best type in this group. The plants have finely cut leaves and bear large flowers variously coloured in white, yellow, scarlet, orange, purple, mahagon in the form of a ring. Disc appear at the centre and upper part of the petals. Annual chrysanthemums are free flowering and grow in all types of soil in sunny situation in beds or pots and used as cut flowers.

  23. Cleome Spinose (Capparidaceae) Spider Plant

  24. The plants are tall (1.0 to 1.3 m) much branched and spiny long protruding stamens and the four petals resemble spider, and the flowers are borne in large clusters at the end of the main stem and branches. In the plains it can be grown in winter and summer and flowers appear within 3 months after germination of seeds. Seeds are sown in September-October and January-February for winter and summer flowering respectively and seedlings are transplanted 40-60 cm apart. Colour of flowers are pink, rose and white.

  25. Cosmos Bipinnatus (Compositae) Cosmea, Cosmos

  26. It is a free flowering popular annual, used for bedding, in mixed border and as cut flower and grows well in sun and semishade in al types of soil. Though cosmos is known as a winter annual, it flowers early in the season, beginning from September and continues till March. The plants are tall (80-120 cm), much branched with feathery foliage and bear large flowers in pink, rose, crimson, lavender or white in colour. There are varieties with double flowers. Cosmos is best sown in situ though transplanting is not uncommon. Early sowing can be done in June-July in low rainfall areas and flowering commences in 2 1/2 months.

  27. Delphinium (Ranuculaceae)

  28. Perennial delphinium though widely grown in the hills, is found to grow well as annual in the plains of northern India. Most of the cultivated varieties are hybrid between D.elatum and other species like D.formosum,D.cardinale, D.belladona and D,nudicaule. Perennial delphinium is tall (1.5 m) much branched with lobes and cut leaves, flowers appear on erect stout spike and colours include white,pink,lavender,lilac,purple pale and deep blue. Delphinium is ideal for mixed border, background and cut flowers. It is propagated from seeds, division and cuttings, the last two methods are only possible in the hill where it is grown as perennial.

    Larkspur, cultivated in gardens consists of two species D.ajacis, the hyacinth flowered and D.consolida the stock flowered larkspur. The plants are tall (80-120 cm), erect, branched with fine feathery foliage. Spikes of blue, purple,lilac,salmon rose or white flowers,singly or double arise in large number. Larkspur is excellent as cut flower and for growing in mixed border, along hedges and in semishade.

    Seeds are sown in October-November, in the plains germination is better in lower temperature. In the hills it can be sown in March-April or during August to October. Larkspur shows satisfactory growth and flowers in well-drained light soil and takes about 3 months to bloom.

  29. Dianthus Barbatus (Caryophyllaceae) Sweet Willam

  30. Sweet william has both annual and biennial strains. Annuals are grown in the plains, while biennials are grown in the hills. Annual varieties are 20-35 cm tall, have dark green foliage and flowers single or double in large rounded and showy clusters at the end of the branches. The flowers have a wide range of colours white, maroon, purple red pink, purple, rose pink, etc., self-coloured or zoned and variously coloured.

    Sweet william is widely grown in the plains and hills in beds, borders and are good for cut flowers. The seeds are sown in September to October and the seedlings will flowers during December to March. Biennial varieties take longer time to flower than the annual ones and are usually grown in hills.

  31. Dianthus Caryophyllus Carnation

  32. Carnation is one of the most popular annual grown in Garden; excellent for bedding, herbaceous borders, edging, pots and as cut flowers. In plains carnation is grown as a winter annual but cultivated as a perennial in hills. They grow and flower well in loamy soil and under full sun. Propagation by seeds and stem cuttings.

    Plants are medium tall, about 40-90 cm high. Stems grey green, narrow with swollen nodes. Leaves narrow, thick and often curves at the tip. Flowers single or double with smooth or fringed edged petals, sweet fragrance like cloves.

    Terminal flowers are white, cream, yellow, pink, rose, red, scarlet, crimson, purple, maroon, orange etc. with selfs, striped, flaked and combination of different colours. Seeds are sown during August-September in the plains to get flowers from February, Flowering starts in 5 months from germination.

  33. Dianthus Chinensis, Indian Pink

  34. Dianthus is one of the most popular and beautiful garden annuals. The plants are 15 to 35 cm high and bear large rounded head of flowers, self-coloured in white, pink, rose, scarlet, crimson, violet, maroon, mauve, purple, etc. or zoned,spotted or blotched in various colours. There are town types of Dianthus-Heddewgii or Japanese pink and the fringed pink. The Heddewgii varieties are dwarf (15-25 cm) plants, free flowering, attractively coloured with single and double flowers having fringed and beautiful margin. The laciniatus varieties are taller (30-35cm), flowers single or double beautifully coloured with finely fringed petals.

    The pinks are excellent for beds, border, rock, gardens and cut flowers. They grow and flower well in loamy soil and full sun. seeds are sown during September-November and the seedlings bear flower about 3 months.

  35. Helianthus (Compositae) Sunflower

  36. The different varieties of sunflower grown for garden decoration can be grouped into two species-Helianthus annus and H. dubilis. Height of H. annus vary from 60 cm to 2.5 metres. Large single yellow flowered and large chrysanthemum flowered varieties are common. There are also large double flowered varieties plants of medium or dwarf height. Plants during the summer has chocolate, bronze or wine red flowers. A strain producing chocolate, bronze and wine red flowers are very attractive and popular in gardens.

    Miniature or Japanese sunflower belongs to the species H. dubilis. The plants are much branched, bushy, 120 cm in height and bear small yellow flowers. Sunflowers can be grown as summer and rainy season annuals for beds and borders. The seeds are sown from January-June and the seedlings transplanted after about 3 weeks. The seeds may be sown in situ.

  37. Impatiens Balsamina (Balsaminaceae) Balsam

  38. Balsam is a popular flowering plant in this country and widely grown in summer and rains. The plants are 20-60 cm tall usually branched and bushy and bear large number of single, semi-double or double flowers. The colours may be white, pink, rose purple, crimson, blue mauve and in various shades and also striped. Camellia flowered type is the best. Dwarf varieties (20-25 cm high) bear large number of flowers on the main stem and branches and make a beautiful display of colour.

    The plants grow well in rich, porous but moist soil and in high humidity in sunny places. They can also be grown in semishade. The seeds are sown in January-February for summer flowering and in May-June to obtain blooms during the rains. In case of Balsam, best method is to sow the seeds in situ and thin out the seedlings. Transplanting can also be done.

  39. Myosotis Alpestris (Boraginaceae) forget-me-not

  40. The plants are 30-40 cm tall, much branched, bushy and bear cluster of small flowers at the end of the branches. Colour of the flower is white, pink, sky blue or dark blue. Myosot is flourishes well in pots and beds and can be grown in rock garden ad mixed borders. Seeds are sown in September-October in the plains and flowering starts after about 5 months.

  41. Petunia Hybrida (Solanaceae) Petunia

Petunia is a popular and colourful annual commonly grown in beds, herbaceous border and in pots and window boxes. The plants may be 20-35 cm in height with trailing branches and produce many funnel-shaped flowers. There are various types of petunia, which show marked difference in growth, size, shape and colour of the flowers.

  1. Bedding—Hardy, free flowering type, bearing numerous small (4 cm across) funnel-flowers. The colours are white, pink, blue, violet, rose and red.

  2. Grandifloras—This type is a comparatively low-growing plant and produces large (10-12 cm) single flower of attractive colour. The edge of the flowers is smooth, frilled or ruffled.

  3. Doubles—Double petunias are magnificent flowers. The plants are widely grown in beds, border and pots. In the plains seeds are sown during August to October. The plants flower well in rich, porous soil and require 3-4 months to initiate flower. Doubles are also propagated vegetatively in the hills. In Japan, USA and Europe all double petunias are being produced by hybridisation.

  1. Phlox Drummondii (Polemoniaceae) Pholox

  2. Phlox is a popular annual throughout the world. It is widely grown in beds, border, pot, boxes and rock garden. The types include Grandiflora with large flowers, Nana compacta having dwarf growth habit and star type producing star-shaped flowers. Many colours exist in grandiflora- white, light yellow, pink, rose, scarlet, crimson, dark blue, violet blue, violet etc.Nana compacta and star type produce compact bunch of flowers. Phlox is easy to cultivate and flowers well in rich soil. Seeds are sown in August-October and seedlings begin to flower with 3 to 3 1/2 months.

  3. Pimpinella Monoica (Umbelliferae) Lady’s Lace

  4. It is a tall growing annual (130-180 cm) with finely cut foliage and bearing small white flowers on loose heads at the end of the branches. Lady’s face is grown in borders and in shrubbery. The flowers are commonly used for floral decoration. Seeds are sown in September-October and the seedlings flower in about 3 months.

  5. Salvia (Labiatae) Sage

  6. Three species of Salvia are often grown as annual in this country-Salvia splendens, S. coccinea and S.farinacea. S. splendens is commonly known as scarlet sage. Height of the plant may vary from 20-70 cm depending on the variety. Bright scarlet flowers appear on long spike at the end of the branches, other colours include salmon, pink and violet.

    S. coccinea—Several varieties of this species bearing red, scarlet, pink or white flowers on terminal spikes are grown in Southern India.
    S. farinacea—The plants are 50-70 cm high, produces spikes of small blue or white flower. Salvia, particularly S.splendens is widely grown in garden for bedding, in border, pots and the dwarf variety in rock garden. It can be grown in semishade.

  7. Tagetes (Compositae) Marigold

Marigold is a popular name among the flowers. There are two common types of marigold, African (Tagetes erecta) and French (Tagetes patula). It is widely grown in beds, pots, rock gardens and as cut flower for making garlands, bouquets and also for worship.

  1. African Marigold

Many varieties of African marigold have been evolved, which show variation in the height of plant, shape and size of flower. The height of plants ranges from 60-100 cm or more, colours are lemon yellow, golden yellow and orange and recently another colour nearest to white is also available. Size of the flower may vary from 5 to 15 cm, carnation flowered type normally produces large flowers. Dwarf chrysanthemum flowered varieties are very useful for bedding. F1 hybrids are superior to the common varieties.

ii. French Marigold

French marigold is a popular flower throughout the world, having a wider range of colour than the African type. It grows very easily, plant has dwarf, bushy growth (10-32 cm high) almost rounded in shape and bears large number of flowers of attractive colour. The flower colour may be yellow,golden,rusty red, mahagony, orange, deep-scarlet and often blotched, stripped or spotted in different colours. The heads may be single or double.

Although marigold can be grown throughout the year, mild winter is favourable for its growth and flowering. Hence, it is widely grown in the winter months in the plains and the seeds are sown in September-October. In the hills, sowing is done in March-April. French marigold flowers profusely in porous soil. While growth and flowering in African type are better in rich and moist soil.

  1. Zinnia ElEgans (Compositae) (Zinnia)

It is a popular flowering annual for summer and rains. There are many types and numerous varieties in zinnia varying in the plant height and size,shape and colour of flowers. The height may vary from 25-100 cm or more. Some popular types are Dahlia flowered. Burpeeana,Giant of California, Haageana. Thumbelina, Cupid, Lilliput and Joni Thumb. Colour of flowers may be white, yellow, pink, rose, orange, scarlet, violet, red, lilac, etc. and size of flowers may vary from 3-12 cm.

F1 hybrids have vigorous growth and are tree flowering. The seeds of zinnia are sown from January to June for flowering during summer and rains. First flower bud appearing on small seedling is removed to induce branching. Zinnia grows well in light soil, rich in organic matter. The seedlings may be transplanted or the seeds sown in situ. The plants are highly susceptible to leaf curl virus in the plains.

Zinnia linearis is a dwarf and bushy plant, reaching a height of 20-25 cm. It grows well in winter and summer and produces numerous small white or orange flowers. The plants are very suitable for growing in beds, border and pots and continue to flower for several months.


Ag.
Technologies
(Horticulture)