MONTANE SOUTH AFRICAN GRASSLANDS AS A NEW PLANTING DESIGN FORM IN URBAN GREENSPACE BY: ZULHAZMI SAYUTI A THESIS SUBMITTED TO THE FACULTY OF SOCIAL SCIENCES STUDIES IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF LANDSCAPE UNIVERSITY OF SHEFFIELD UNITED KINGDOM June 2013 Contents ABSTRACT The aims of this study were to develop communities of South African montane grassland species as a new planting design form in urban parks and green spaces. The uniqueness on the canopy texture and structure additionally the attractiveness produced from colorful flowers, from spring, summer and autumn potentially give strong design impact. To develop the community for use in urban greenspace three series of experiment were conducted to investigate time of sowing, growth performance, winter hardiness, competition in communities and appearance. Most of the species show good emergence and growth performance when sowing seeds directly in the field between March and May. Pre- germination treatments did speed up germination post sowing in the field but do not result in a significant increase of emergence percentage compared sown directly. Studies on species hardiness during extreme cold winter in 2010/2011 on different types and depth of media (sand 70 mm, sand 140 mm and soil 70 mm) found that increase in depth of mulch decrease the survival of the species on sand. Increased seedling mortality was due to lower root zone temperatures in the deeper sand with ambient temperatures as low as -8.7 °C. Most of the species sown in soil shows a better survival than sown in sand. Greater soil wetness in soil was less hostile to overwintering survival than was the lower temperatures associated with the sand treatments. Evergreen species such as Dierama robustum, Berkheya multijuga, and Senecio macrospermus overwintered well and Gladiolus saundersii is one of the hardiest species in this experiment. In the competition experiment, forbs species were the most productive in producing biomass and % cover in every community. Berkheya purpurea is a highly productive species and dominant in the first and second year of this study and greatly affected the production of biomass and canopy coverage in the communities it was present in. The communities with forbs species in combination produced 50% cover faster approximately 50 days after spring cutting in the second year. The geophytes species had much less influence on the biomass and % cover in the community, at least in the first two years. Even though Kniphofia uvaria also able to produce high biomass but does not greatly increases % cover due to the canopy structure being more open. However, the combination of species with different canopy layers is a very effective spatial arrangement for naturalistic design. High germination percentage as well as good growth in the first and second years of study showed that most species are able to survive and flower ii Contents well in the UK. Most of forbs from low canopy species flower early in the season on the first and second years while geophytes species with slow growth, medium and tall canopy flowering from mid-season until a late season. Based on the results of these studies it appears that South African montane grassland have good potential to be used as a new planting design in UK urban greenspace iii Contents DECLARATION No portion of this work referred to in this thesis has been submitted in support of an application for another degree or qualification of this or any other university or institute of learning. iv Contents ACKNOWLEDGEMENT It is a pleasure to thank those who have contributed and extended their valuable assistance in the preparation and completion of this study. First and foremost, I offer my sincerest gratitude to my supervisor, Professor James Hitchmough, for his supervision, knowledge and encouragement throughout my study and thesis writing. His academic experience and practice has been my inspiration in the completion of this research, through insightful discussions and suggestions. This thesis would not have been possible without his help and guidance. I have successfully overcome many obstacles in completion of this study, through his support and guidance. I take this opportunity to sincerely acknowledge the Malaysian Agriculture and Research Development Institute (MARDI) for providing financial support during my study. My special thanks to all the academic staff of the Department of Landscape for their views and critical comments during the upgrading presentation and the PhD symposium. To the administrative and technical staff at the Department of Landscape, I offer my heartily thankful for all of your support and assistance during the study. Special thanks to Ms Jane Russell for her guidance on data analysis and Dr. Zoe Dunsiger for the insights she has shared in discussions regarding my project. I expand my special thanks to all technical staff in Sheffield Botanical Garden for helping me during field experimental. Furthermore, I would like to thank all my friends and colleagues, especially my friend who assisted me in experimental setup and data collection, thank you very much for your help. Special thanks dedicated to my mom Sapura Hisan and my family, for their constant source of support emotional and moral throughout my postgraduate years. Last but not least, I would like to express my special thanks to my lovely wife, Rafeah Mat for your assistance to me during this academic study and living in the UK. Your patience, understanding and cheering deserve a special mention here. Not forgotten, my daughters Nur Farzana, Nur Fatini and Damia Azhani for their love, joy and my inspiration. Without all of them this would not be possible. Alhamdulillah. v Contents CONTENTS Page Abstract ii Acknowledgements v Contents vi List of Figures xiii List of Tables xix CHAPTER 1: INTRODUCTION 1.1 Background 1 1.1.1 Naturalistic planting design approach 3 1.1.2 Climate change in the UK in relation to climate of South Africa Grassland 4 1.1.3 Overall aim of the research 7 1.1.4 Research questions 7 1.1.5 Research objective 7 1.2 Research activities 8 CHAPTER 2: GERMINATION, ESTABLISHMENT AND COMPETITION IN SOWN PLANT COMMUNITIES 2.1 Factors affecting seedling establishment 10 2.1.1 Intrinsic factors affecting germination and emergence 11 2.1.1.1 Seed quality 11 2.1.1.2 Seed size and uniformity 12 2.1.1.3 Seed dormancy 13 2.1.1.4 Overcoming these intrinsic limitations to germination in practice 14 2.1.2 Extrinsic factors affecting germination and emergence 15 2.1.2.1 Temperature 15 2.1.2.2 Water 16 vi Contents 2.1.2.3 Light 17 2.1.2.4 Effect of sowing practice on these factors 18 i) Sowing time 19 ii) Sowing depth 20 iii) Type of substrate 21 iv) Use of sowing mulch to control weeds 21 v) Rolling after sowing 22 vi) Irrigation post sowing 22 2.2 Competition in plant communities 23 2.2.1 Plant growth rate 23 2.2.1.1 Relative growth rate 23 2.2.2 Competition in sown communities 24 2.2.2.1 Competition for water 26 2.2.2.2 Competition for soil nutrients 28 2.2.2.3 Competition for light 29 CHAPTER 3: EFFECT OF SOWING TIME AND GERMINATION PRE-TREATMENT ON EMERGENCE AND BIOMASS PRODUCTION OF SOUTH AFRICAN SPECIES IN THE FIRST GROWING SEASON 3.1 Introduction 31 3.1.1 Objectives 32 3.2 Materials and methods 32 3.2.1 Pre-germination treatment 34 3.2.2 Data collection 35 3.2.3 Statistical analysis 36 3.3 Results 3.3.1 Effect of time of sowing on seedling emergence and establishment of species in June and August 2010 38 vii Contents 3.3.2 Effect of pre-germination treatments versus sowing seed directly into the experiment on seedling emergence and establishment of species in June and August 2010 38 3.3.3 Effect of sowing time and sowing treatment on emergence of species in different rate of germination groupings 39 3.3.4 Effect of time of sowing on seedling emergence and establishment of each species in June and August 2010 41 3.3.5 Summary of results of each species 43 3.3.5.1 Fast germinating species 43 i) Galtonia candicans 43 ii) Helichrysum aureum 43 iii) Diascia integerrima 43 iv) Berkheya purpurea 43 v) Gazania linearis 43 vi) Helichrysum pallidum 45 vii) Eragrotis curvula 45 3.3.5.2 Medium speed emerging species 45 i) Aloe boylei 45 ii) Kniphofia triangularis 45 iii) Agapanthus inapertus 45 iv) Gladiolus papilio 47 v) Hesperantha coccinea 47 vi) Agapanthus campanulatus 47 vii) Watsonia latifolia 47 viii) Crocosmia masonoirum 47 ix) Moraea huttoni 47 x) Tritonia drakensbergensis 49 3.3.5.3 Slow emerging species 49 i) Watsonia pulchra 49 ii) Gladiolus oppositiflorus 49 iii) Dierama pulcherrimum 49 iv) Dierama latifolium 49 viii Contents 3.3.6 Effect of sowing seed directly and pre-germination treatment on seedling emergence and establishment by June and August 2010 51 3.3.7 Effect of sowing time on biomass of species by 60 days after emergence 52 3.3.8 Effect of pre-germination treatment and sowing seed directly on biomass by 60 days after emergence 54 3.3.8.1 Dry weight 60 days after emergence 55 3.3.8.2 Dry weight of each species 56 3.3.9 Effect of sowing time on biomass of species 150 days after emergence 57 3.3.9.1 Effect on species in speed of germination groups 57 3.3.9.2 Dry weight of individual species 150 days after Emergence 58 3.3.10 Effect of sowing seed directly and pr-germination treatments on biomass of species by 150 days after emergence 59 3.3.10.1 Effect of pre-treatment after 150 days on individual Species 60 3.3.11 Relative growth rate 61 3.4 Discussion 65 3.4.1 Sowing time and seed emergence