Growing of Perennials - NOTES

                                                          UNIT 4

                                       Growing of Perennials

 The very first memories about your schooldays will be about playing or chit chatting with friends around a Gulmohur or  Manchadi  in the school premises. These beautiful trees make a pleasant appearance for the homes, institutions, and public spaces around us.

                Polyalthea  trees  providing a better appeal for the school compound.

Such plants with more than 2 years of lifecycle are called perennial ornamental plants.

eg: Asoka,  Cassia fistula(Kanikkonna), Elenji, Hibiscus, Ixora, Bougainvillea,

 Types of perennial

 Perennial ornamental plants are classified into 2 main types:

1. Woody perennials:-  trees, shrubs and vines having woody stem.

           Eg:  Cassia fistula, Hibiscus,Duranta,Phyllanthus, bougainvillea

2. Herbaceous perennials:- plants with soft and herbaceous main stalk

          Eg: Anthurium, Orchids, Heliconia, Gerbera.

  Uses of Perennials

Trees used as avenue plants.

Provide an aesthetic appeal for our surroundings

For natural screening of a place for privacy

Herbaceous perennials used as hedges, borders etc.

Some Perennials produce fragrant flowers refreshing the air,  eg: Ilang Ilang tree.

They have medicinal values.

 

                                                        ORNAMENTAL TREES

Trees cultivated for gardens and parks with woody  trunk and grow for several years.

Importance

1.       Landscaping and avenue planting.

2.       Main frame work of the garden

3.       Control air pollution

4.       Produce attractive and beautiful fragrant flowers

5.       Produce attractive foliage

6.       Used as specimen trees

 

 

                                               Tree as a major component of a home garden

 

Classification of ornamental trees

1.       Flowering trees : Cassia fistula, Champaka, Asoka, Gulmohur

2.       Non flowering trees : Banyan tree,  Eucalyptus, Polyalthea,Maple tree

  Gulmohur(Vaka) : a flowering tree                                       

 Fiddle leaf tree: a foliage tree

 

                          Cultivation Practices of Ornamental Trees

Propagation:   Trees are harder than other ornamental plants.  Healthy rooted seedlings are the commonly used planting material.  It is advisable to plant 2-3 year old seedlings than young.

Soil type: generally trees prefer well drained loamy soils rich in organic matter.soils having frequent water stagnation,high acidic and alkaline P^H are not suitable.

Pit size: Depending on plant size, pits measuring 60cm³ to 1 m³ are prepared for planting trees for vigorous growth.

Planting:   The dug up soil is mixed with at least 4 to 10 kg of well rotten FYM or leaf mould.  After 3-4 days, plant the tree keeping the ball of earth around the roots.  After pressing the soil firmly around the newly planted tree with both the hands, water and stake the plant. Take protection against termites and chaffer beetles or grubs by adding neem cake into the pit.

Time of planting:  Planting should be done during the end of the hot summer and near to the onset of monsoon. Sometimes the planting is also done after heavy rains.

Spacing: Dwarf trees are planted 5 m apart in the rows, and taller and spreading trees are planted 10-12 m apart. A tree with huge canopy such as banyan tree or rain tree can be planted further apart.

Manures and Fertilisers:  Soil nutrient management is very essential for the proper plant growth,productivity and health of the soil.  Organic manures like FYM or compost applied @ 10 -50 kg per tree with the onset  of monsoon. Application of essential nutrients through chemical fertilisers has a very good impact on proper tree growth. Manures and fertilisers are applied in trenches 30 cm deep taken at a distance of 1m from tree base.

Irrigation: Irrigation may not be necessary in grown up trees. However during early stages and in drought, irrigation has better effects on tree growth.

 

Management and care of transplanted trees/Special cultural practices in trees:

1.        Staking : newly planted tree seedlings are prone to toppling by the wind. A stake which is  often a metallic rod is positioned close to  the stem will keep the plant upright. Tying should permit some degree of movement with the wind.

2.       Wrapping : trees often need to be protected against damage from intense sunlight and cold during first 2-3 years after transplanting. Covering using palm leaves or even with paper around the trunk give necessary protection.

3.        Trunk painting : Trees trunks may be protected against heat damage by sunlight by painting at about 6-12 inches of the base of the trunk with diluted  lime.

4.        Mulching : a mulch should be placed around the base of the stem to  retain soil moisture. Mulching also prevents the soil from cracking and aids in soil infiltration by water and rapid root development.

5.       Installing a berm: after firming the soil, a water retaining wall or ridged structure called a berm may installed by using the excess soil to form a ring around the trunk. These structure forms a basin to hold the water around the base of the tree.

6.       Pruning : in bare root seedlings,thinning of the top reduces the dangers of toppling by wind. Because of root mass loss, seedling need heavy pruning to minimise the water loss.

7.       Training: it is a practice in which tree growth is directed into a desired shape with strong framework. Usually carried out in young plants.

8.       Anti transpirants :  to reduce  transplanting shock, anti transpirants may be sprayed with a foliar application before transplanting. Eg. ABA,Aspirin.

9.       Installing a wire mesh : to protect against pest such as rodents and grazing animals.

 

SHRUBS

                            .

Ornamental shrubs are perennial plants with a woody stem and smaller plant stature compared to trees. They are distinguishable from tress in several features:

1.       Height : shrubs are usually low growing (less than 3 m)

2.       Central axis: trees usually have a main trunk. Shrubs produce multiple stems from a lower crown

3.       Size: shrubs are smaller and require less space than trees.

4.       Branches : shrub branches more profusely than trees, starting low on the stem

Uses of shrubs/purposes of growing shrubs in gardens

 1. shrubs enhance the beauty of gardens

2. They are used to make live boundary walls for gardens.

3. Used for screening unwanted  places like manure pits, store rooms etc.

4. Shrubs are planted to divide areas in gardens like children’s corner.

5. They produce fragrant flowers and refresh  air .

1.  Classification of shrubs:

 

1. Flowering shrubs: produce attractive flowers, used for mass effect and carpeting.

     Eg: Ixora, Hibiscus, ,Calliandra(powder puff).

2.  Foliage shrubs: These shrubs are grown in gardens for their beautiful foliage.

     Eg: Acalypha,Duranta, Phyllanthus.

3. Shrubs for flowers and foliage: Eg: Bougainvillea, Hamelia(firebush or                          

     Scarlet bush)

4. Shrubs for fragrant flowers: Eg: Jasminum sambac(Kuttimulla),

 

Cultivation practices of ornamental shrubs:

Propagation: Shrubs are propagated mainly using rooted cuttings, seeds and by layering.

Cuttings: Hibiscus, Hamelia, Jasminum sambac.

Seeds: Thevetia,Calliandra,Caesalpinia

Layering: Ixora, J.sambac, Bougainvillea

Soil: Any fertile garden soil is suitable for shrubs. Soil P^H should not be highly alkaline or acidic.  Planting season: The best planting season for shrubs is the rainy season, ie by the onset of monsoon.

Spacing: Planting distance vary according to the height and spread of the plant. It ranges between 0.5m to 2.5m.

Manures and fertilisers: 45 kg of FYM per pit is applied after mixing with top soil. It will be beneficial if a handful of bone meal is added during planting. Foliar application of nitrogen is beneficial for foliage shrubs.

Irrigation: Shrubs need watering regularly depending upon season and soil texture. During summer season, irrigation given once in 7-15 days interval.

Important cultural practices in shrubs:

1) Pruning: Shrubs need careful pruning. Shrubs like hibiscus may need little pruning. When shrubs have been grown as hedge, they need shearing. In tropical region best time for pruning is before rains and in cold countries after spring flowering. Large shrubs need pruning to check growth and small shrubs need pruning to encourage flower. All dead and weak branches are removed from its base.

2)Weeding: weeds should be removed to avoid competition for nutrients and water. During rainy season weeding at 2 weeks interval is essential.

TOPIARY:

The art of clipping and shearing perennial ornamental plants into beautiful shapes is known as topiary. Plants which have numerous dark green foliage are suitable for topiary work.

It is possible to attain shapes of different types. Simple shapes such as a globe, sphere, dome, table, chair, and cube are not very difficult to achieve, but when figures of birds or animals are to be shaped, a lot of patience is needed. Difficult shapes such as bird, animal etc are to be obtained by preparing a rough outline with wires and then training the shrub along the frame and clipping carefully over years to get the desired shape. The branches are tied carefully to the frames without causing any injury.

            

 In India the Hanging gardens or Kamala Nehru park of Mumbai is famous for its Topiary work. The shrubs most commonly used in India for topiary are Clerodendron inerme and Duranta plumier. Other shrubs used are Bougainvillea, Murraya exotica and species of Hibiscus.

 

Birds, animals - Bougainvillea, Duranta

Domes, cones, spheres, umbrellas – Thuja, Polyalthia

 

CLIMBERS AND CREEPERS

               A climber is defined as plants which possess special structures to climb over a support. Those special structures may look like thorns (Eg: bougainvillea), tendrils (Antigonon), rootlets (Ficus repens) or modified leafstalks. Creepers are those plants which are unable to climb vertically on their own, because of their weak stems. They do not have special structures for climbing on a support. Eg: morning glory.

 

            Climbers are important ornamental plants; they enhance beauty of a garden to a great extent. They can be used for the purpose of screening to maintain privacy from the adjacent houses. They also can be grown over specially constructed pergolas, arches, pillars or similar structures. They are most suited for roof garden, where lack of space is a problem.

 

Classification of climbers

1.       Showy flowering climbers - Antigonon, Bogainvillea

2.       Shade loving climbers        - Monstera, Pothos

3.       Climbers for pots                  - Bogainvillea, Clitoria ternatea

4.       climbers for hedge making – Clerodendon

Cultivation Practices

In general, all climbers need fertile and deep loamy soil with good drainage. Generally pits of 60cm³ is prepared and refilled with well rotten FYM. Regular watering should be done after planting. Climbers do not grow vertically without support. Therefore they should be supported by tying  with strong strings or fine wires. Some climbers need pruning. Manuring wit FYM once in a year just before monsoon should be done. Application of bonemeal once during monsoon is also beneficial.

Propagation - 

Use of  cuttings and  layers is the common method of propagation.

Adenocalymma alliaceum ( garlic vine)- propagated by cutting or layering.

Allamanda – by cutting or layering

Bogainvillea - cuttings,air layering and budding.

PERGOLAS

A pergola may be defined as a series of arches joined together. Pergolas are generally constructed over pathways which add beauty to the garden. The width of pergolas is kept generally within 2-2.5 m and the height is also same but preferably on the higher side. The length will depend upon the area to be covered. The roof of a pergola may be flat or in the shape of an arch. The path below remains cool due to the climbers growing above.