Chapter – 4
Selection of Plant Material for Landscape
(Sudhir Kamal Seem, M. Arch. (Landscape), Senior Architect, CPWD)
The success of landscape design with plants depends on how to choose the appropriate plants for a particular situation. Thoughtful selection of the trees, shrubs, climbers, bulbs, foliage plants, grass, groundcover and aquatic plants transform the barren landscape into meaningful landscape. Efforts should be made to select an appropriate plant material for the given situation based on the following criteria :
(i) Habit
(ii) Colour
(iii) Season of flowering
(iv) Form
(v) Rate of growth and Environmental considerations.
1. Trees:The selection of trees should be based on season, size, form, situational preferences of surroundings and artifacts.
1.1 Flower Colour
White : Alstonia scholaris, Baiiasea minor, Magnolia pterocarpa Milingtonia horternsis and plumeria acurmnaata.
Yellow : Cassia fistula, Bauhinia tomentosa, Saraca indica, Peltophorum pterocarpum and Tabebuia spectabilis.
Red : Bombax ceiba, Amberstia nobilis, Cassia marginata
Scarlet : Barningtonia monandra, Cassia pavarnica Crennigena, Kelnbovia hospita.
Purple : Lagerstroemia speciosa, Bauhinia purpurea, Melia azadirach, Pachira, rosea and Tabebuia rosea.
Orange, Red, Crimson, Scarlet : Butea monosperma, Colvia racemosa and spathpdea campanulata.
Blue, Mauve, Violet : Jacarpanda aquisatifolia, Guaicum officinale, Millenia avaliolia and Solanum grandugkirum
Greenish Yellow : Monodora grandiflora.Casealpnia,
Creamy White or Yellow : Michelia champaca, Madhuca Indica, Magnolia grandiflora, and Terminalia Arjuna.
1.2 Season of blooming
Ever blooming : Callisetermon lanceolatus, Mimusops elengi, Plumenia acuminata and Thespesia populnea.
Winter blooming : Bauhinia purpurea, Butea monrosperama. Monodora grandiflora
Spring blooming : Tabebuia, Amheristia niobilis, Bombax ceiba, Jacaranda, Saraca indica, Spathodea
Summer Blooming : Erithrina indica, Cassia, Jacaranda, Lagerstroemia spp.
Rainy season Blooming : Plumeria alba, Anthocephelus cadamba, Barringtonia raccemosa, Casia Marginata, P. rubra, Covillea raccemosa.
1.3 Range of Tree sizes
Dwarf trees (3 to 5m tall) : Albizia lebbek, Bisantha, Bixca orellana, Brownera grande eps, Crodia sebestena. Wevthrnia blackein Parkinsonia acuminata, Plumeria rubra.
Medium size (6 to 10m tall) : Caesalpinia, Lagerstromia throreli, Melia azadirach, Plumeria accmnata, Saraca Inidica, Tabeulia spectabilis.
Tall tress (more than110 m tall) : Peltophorum roxburghii, Bombax malabaricum, Cassia monisia, Chorisia speciosa, Jacaranda, Millingtonia hortensis, and spatholea campanulata.
Giant trees : Ficus bengalensis, Bombax ceiba, Colvillea racemosa,
1.4 Growth Habit of Trees
Oval : These plants are suitable for frame or screen. Populus alba, Albizzia julibrissin, Crataeqs cerusoalli Cornus sp., Betula pendula Cassia fistula
Vase shaped : They can be used above the large shrubs or small trees. Melia azadirach, Plumeria acutifolia. P.alba. P.obtusa, Saraca Indica. Almus Americana.
Pyramidal : It can be used as an accent plant. Pinus roxburghii, Araucaria cooki. Thuja compacta, Quercus palustris, Stercula foedtida, Polyalthia longifolia.
Round : These plants can be used in the lawn as specimen. Plumeria alba,Chorisia speciosa Mimusops elengi. Morus rubra, Quercus.
Columnar : They frame the views and structure in the landscape setting. Juniperus chinensis, Betula pendula, Quercus robustaj Eucalyptus robusta, polyelthia pendula.
Weeping : It can be used as a focal point. Salix Babylonica, S. alba. Putranjiva roxburghii, callistemon lanceolatus Tecomelia.
Round to spreading : These plants mass well to create grove effect. Dalbergia sisso, Dillenia Indica, Ficus glomerata, Thespesia populnea.
Fan shaped : They can be used as a focal point. Cycus revoluta, Borassus fladellifer, Oredoxa regia.
1.5 Trees with scented flowers : Anthocephilus cadamba, Alstonia scholaris, Cananqium odoratum Michelia champaca, Mimusops elengi, Dillenia indica, Gardenia latifolia, Custravia augusta, Magnolia grandiflora, Nyctanthes arbortristis.
1.6 Wind Resistant trees : Eugenia jambolana, Caesalpinia pulcharima, Peltophorum pterocarpum.
1.7 Salt Resistant trees : Azadirachta Indica, Acacia sp., Butea monosperma, Azadirachta. Indica, Bassia Latifolia, Eucalyptus citriodora, Phonix dactylofera and Phyllanthus emblica.
1.8 Drought Resistant : Butea monosperm, Acacia sp., Albizzia lebbek. Casuaria equisetifolia. Crataeva religiosa. Tecomelia.
1.9 Wet Land trees : Nyctanthes arbortristis, Dillenia Indica, Michelia champaca, Saraca Indica, Thespesia populnea, Salyx Babylonica, Ecualyptus eostata, Guaicum officinalis.
1.10 Fast Growing Trees : Pongamia glabra, Sesbania grandiflora, Cananqium odoratum, Erithrina Indica, Thespesia populnnea, Populus sp., Salix sp,. Euclyptus sp., Thuja compacta.
1.11.Shade givers : Pteropsperum acerifolium, Albizzia lebbek, Pelptophorum, Michelia champaca, Anthocephalus cadamba, Dalbergia sisso,. Glyricidia Maculata accer sp., Cornus florida.
1.12. Trees tolerant to Dust and Smoke : Acacia auriculiformis, Alstonia soholaris, Butea monosperma, Ficus Benjamina, F. benghalensis, Madhuca Indica, Pongamia glabra, Ficus religiosa, Terminalia Arjuna, Albizzia llebbek, Bombax ceiba.
1.13. Trees for Noise Reduction : Terminalia Arjuna, Alstonia scholaris, Azadirachta Indica, Butea Monosperma, Mangifer Indica, Madhuca Indica, Juniperus chinesis, Eucalyptus Citradora, Kigelia pinnata
Chapter – 5
Plants and Indoor Air Quality
(P.S.Sodhi, M. Arch. (Landscape), Architect, CPWD)
Indoor Air quality plays an important role in the work performance and the health of the users. With the passage of time the indoor levels of pollutants increases, sometimes much higher than the outdoor levels. To mitigate these effects a study was undertaken by IIT, TERI and learning’s from NASA that there are number of common green plants, with which we can grow all the fresh air we need indoors to keep us healthy. Common indoor plants may provide a valuable weapon in the fight against rising levels of indoor air pollution & are very useful in absorbing potentially harmful gases and cleaning the air inside modern buildings and provide a natural way of helping combat “Sick building syndrome”.
The most common three air quality improving plants are Areca palm, Mother-in-Law’s Tongue and Money Plant.
Areca palm is a plant which removes CO2 and converts it into oxygen. We need four shoulder-high plants per person, and in terms of plant care, we need to wipe the leaves every day in Delhi.
Mother-in-law’s Tongue is again a common plant. We call it a bedroom plant, because it converts CO2 into oxygen at night. One requires about 6-8 such waist high plants per person in the bedroom.
Money plant is a very common plant; preferably grows in hyrdoponics. It is excellent plant for removing Formaldehyde and other VOC’s (volatile chemicals) in the air.
The indoor plants most effective in removing Formaldehyde, Benzene and Carbon Monoxide from the air are:
1 | Bamboo Palm | - | Chamaedorea Seifritzii |
2 | Chinese Evergreen | - | Aglaonema Modestum |
3 | English Ivy | - | Hedera helix |
4 | Gerbera Daisy | - | Gerbera Jamesonii |
5 | Janet Craig | - | Dracaena “Janet Craig” |
6 | Marginata | - | Dracaena Marginata |
7 | Mass cane/Corn Plant | - | Dracaena Massangeana |
8 | Mother-in-Law’s Tongue | - | Sansevieria Laurentii |
9 | Pot Mum | - | Chrysanthemum morifolium |
10 | Peace Lily | - | Spathiphyllum |
11 | Warneckii | - | Dracaena “Warneckii” |
All the above mentioned indoor plants can be used to improve the indoor air quality.
Chapter- 6
Process of Planting and Transplanting of Trees
(Sudhir Kamal Seem, M. Arch. (Landscape), Senior Architect, CPWD)
Planting:Definition
Planting is the operation of transferring young plant from nursery to their permanent place in landscape.
Steps Involved in Planting: Site Condition
The conditions of the planting site are as important as the plant. Soil type and drainage, available water and sunlight, exposure to dying winds, and other factors must be considered.
Attempting to match the requirements of the plant to the site increase the survivability, performance, and longevity of the plant selected.
Soil Texture
The first step in assessing the condition of the planting site is to examine the soil. Whether the soil is sandy and well drained, or is it moist with some organic material, or is it heavy dlay and therefore, wet and perhaps compacted.
Construction practices such as cutting and filling, installation of underground utilities, and backfilling against foundations can create great diversity in soil structure. This variability can change drastically with depth and between planting locations on the same property-investigate each planting site.
Soil texture and drainage are closely related. Sandy soils usually are very well drained, have large pore spaces, and poor water- holding capabilities. They are usually associated with dry conditions.
Conversely, clayed soils have much smaller pore spaces, are poorly drained, and can suffocate plant roots. The pore spaces in soil are very important to plant growth because the oxygen that occupies them is essential to healthy roots. A tree planted in poorly drained soil will be slow to establish, lack vigor, and often will slowly die.
Drainage
Because plant roots require both moisture and oxygen for growth, soil drainage should be checked before planting. A poorly drained soil, high in moisture but low in oxygen, prevents both proper root development and growth of beneficial soil micro-organisms that are responsible for decomposing organic matter and releasing plant nutrients.
To test for soil drainage, dig a hole 18 inches deep, fill it with water, and let it stand overnight. If the water has not drained by morning, there is a draining problem. (Do not leave the drainage in this matter after heavy rainfall or before the ground has thawed in the spring).
If soil drainage is inadequate, species that are tolerant of poorly drained soils may be planted, or soil drainage may be improved. This can be done in two ways. If a hard pan is present (a compacted, impermeable layer of soil) with an underlying layer of well – drained soil, a hole can be dug down to the permeable layer to provide drainage for the planting hole.
If the soil is poorly drained and there is no well-drained layer below, a tile system can be laid. However, this is expensive and requires the assistance of a professional for proper design. Simply adding gravel to the bottom of the planting hole will further decrease oxygen availability to the root system.
Compaction of the soil by vehicles or people can reduce pore space and restrict water infiltration, as well as cause physical damage to roots of existing trees. In compacted soil, oxygen is depleted, carbon dioxide accumulates, and root penetration is reduced. This is detrimental to root growth. Aerating the soil will help correct the problem.
Soil pH is a measure of the acidity or alkalinity of a soil. A pH below 7 (7 is neutral) would indicate an acidic soil, and a pH above 7 indicates an alkaline soil. Many plants have an optimal range of pH. Most trees thrive on a pH between 5.5 and 6.5. Soil pH is raised by calcium carbonate or lime. Plant species that will tolerate a high pH should be considered for areas with buried concrete, near foundations, or sidewalks etc.
Before a plant is planted on a particular site, a soil test should be conducted to determine possible pH problems or nutrient deficiencies.
Water
The correct amount of water for plants is essential. Selected plants that are tolerant of excess water for low areas where water may be standing or very close to the surface, or where a heavy clay soil exists. Standing water or a high water table means low oxygen content in the soil. Therefore, trees and shrubs that can tolerate excessive moisture are often better suited to these poor sites.
Sunlight
Although some plants can tolerate low light conditions, most require full sun to maintain their vigor and attain their full potential. Some plants may require some protective shade to prevent leaf scorch and desiccation.
Location
The location of the planting site in relation to other trees and objects such as buildings, fences, etc. will have a considerable influence on temperature and moisture conditions around the tree. Prevailing westerly winds have a drying effect on non-protected sites. The south side of a building will be much warmer and drier than the north side. The warming effect of the sun on a cold winter day can cause injury to the bark and may cause the tree trunk to split. For evergreens, this warming can cause water loss and growth activity resulting in needle damage when the temperature is again lowered Plant hardiness can be greatly affected by the amount of protection provided by individual microclimates.
Planting Season
The season for planting will depend upon the following factors:
1. Adequate amount of rainfall.
2. Presence of moisture in the air.
Planting Procedure:
Preparation of Pit:
Planting the sapling
Staking
Watering
Planting of Shrubs
Transplanting: Definition
Considerations for Transplanting
Season of Transplanting
Site Selection
Transplanting Procedure
Staking:
Trees should be protected from bending due to wind by stakes. Stakes also help in transpiration of water.
Watering
After transplanting, copious watering is done. Copious watering procedure has to be clearly mentioned.
Post Planting Care
Watering
Mulch
Fertilizer
Pruning
Mechanical Support
Root ball sizes for Deciduous Trees: Small Trees:
Height (up to 6 feet) |
Minimum Diameter Ball | Depth |
2 feet | 12 inches | 9 inches |
3 feet | 14 inches | 11 inches |
4 feet | 16 inches | 12 inches |
5 feet | 18 inches | 14 inches |
Root ball size for Deciduous Shrubs:
Height (up to 6 feet) |
Minimum Diameter Ball | Depth |
12 inches | 9 inches | 7 inches |
18 inches | 10 inches | 8 inches |
2 feet | 12 inches | 9 inches |
3 feet | 14 inches | 11 inches |
4 feet | 16 inches | 12 inches |
5 feet | 18 inches | 14 inches |
6 feet | 20 inches | 14 inches |
7 feet | 22 inches | 15 inches |
Root ball sizes for Evergreens Spreading, Semi-spreading and Globe (or dwarf) Types (broad leaf and marrow leaf):
Spread | Minimum Diameter Ball | Depth |
9 inches | 8 inches | 6 inches |
12 inches | 10 inches | 8 inches |
18 inches | 12 inches | 9 inches |
2 feet | 14 inches | 11 inches |
21/2 feet | 16 inches | 12 inches |
3 feet | 18 inches | 14 inches |
31/2 feet | 21 inches | 14 inches |
4 feet | 24 inches | 16 inches |
Cone and Upright Types (broadleaf and narrow leaf):
Spread | Minimum Diameter Ball | Depth |
18 inches | 12 inches | 9 inches |
2 feet | 14 inches | 11 inches |
3 feet | 16 inches | 12 inches |
4 feet | 20 inches | 14 inches |
5 feet | 22 inches | 15 inches |
6 feet | 24 inches | 16 inches |
7 feet | 27 inches | 18 inches |
Columnar Types (narrow leaf):
Spread | Minimum Diameter Ball | Depth |
12 inches | 10 inches | 8 inches |
2 feet | 13 inches | 10 inches |
3 feet | 14 inches | 11 inches |
4 feet | 16 inches | 12 inches |
5feet | 18 inches | 14 inches |
References :
i. Study Material distributed at M.Arch. (Landscape) SPA, New Delhi.
ii. http://landscaping.about.com/ cs /shrubsbushes /ht /transplanting.htm
iii. http:// www.sustland.umn.edu /implement/ treespade.htm
iv. http:// www.lowes.com/ cd_Transplanting +Mature +Trees+ and+ Shrubs
v. American Standard for Nursery Stock
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