Recommended Books
A practical field guide to New Zealand's native edible plants. Andrew Crowe Gardener's Encyclopaedia of NZ Native Plants by Cave, Paddison Trees and Shrubs of New Zealand by Poole and Adams High Altitude Mountain Daisies (Celmisia Semicordata), Mt Cook NP, Canterbury, New Zealand McCormack, Gareth 18 in. x 24 in. Buy this Photographic Print at AllPosters.com | Germination strategies for New Zealand native plant seeds.Seed germination for horticultural use is more of an art than a science. However, many people have experimented with methods of increasing germination success and there is now a body of knowledge which suggests that seeds can be classified into a number of groups, based upon germination strategies. Understanding the groupings may help the propagator achieve successful germination. Note that a species may fall into more than one group. My experiences suggest that - "fresh is best"
- Cold storage makes little impression on successful seed germination other than create a more uniform time of germination.
- The strongest germination occurs shortly after a change in season or a change in temperature. Strongest germination occurs in spring or autumn, when the temperature changes.
- Gather your seeds from a grove or clump of plants, rather than an individual species standing alone. Species prefer to be fertilised by an individual of the same species (cross-pollination) rather than themselves (self-pollination).
There are many exceptions to these classifications.
Vivipary Where germination proceeds on the parent plant. Plants that adopt this feature attempt to have their offspring established well before the inhospitable time of winter. The new individuals are dispersed as growing seedlings. There is no inhibition or delay in germination and embryo development and many features associated with seeds are absent. Avicennia marina Euphrasia disperma Pachystegia minor Corokia macrocarpa Dysoxylem spectible
Recalcitrance A high water content must be maintained even though the seeds may be dormant. Avoid drying out of these species as they will lose their viability if their water content is reduced. These are predominantly trees of tropical origin where the seeds are located within a fleshy fruit. The flesh of these species may become gelatinous with time which may help protect the seed from desiccation in the time necessary for germination to occur. The seeds should be sown as soon as collected and require the persistence of moist conditions. Agathis australis kauri Alectryon excelsa titoki Aristotelia serrata wineberry Beilschmiedia tarairi taraire Beilschmiedia tawa tawa Corynocarpus laevigatus karaka Dacrycarpus dacrydioides kahikatea Dacrydium cupressinum rimu Dodonea viscosa akeake Dysoxylum spectibile kohekohe Entelea arborescens Whau Fuchsia excorticata Kohuhu Gresilinia littoralis Puka Laurelia novae zelandiae Pukatea Myosotidium hortensis Chatham island forget-me-not Nothofagus spp NZ Beech Podocarpus totara totara Ripogonum scandens supplejack Syzgium maire Maire Quiescent Rapid germination following seeds dispersal. These seeds are quick to germinate and should be sown directly on collection. Arthropodium cirratum renga lily Knightia excelsa rewarewa Kunzea ericoides kanuka Leptospermum scoparium manuka Myrsine australis matipo Olearia colensoi Pittosporum eugenoides Phormium Rhopalostylis sapida Nikau Weinmannia racemosa kamahi Weinmannia silvicola Towhai
Dormant seeds These seeds require some form of stimulation from the environment to trigger germination. This may be light or a period of low or a critical temperature. In some species the embryo may not be fully developed at the time of seeds dispersal and a period of after ripening may be necessary before germination occurs. Other species may be dormant because of a biochemical inhibitor in the testa or fruit layers which may restrict water uptake or gas exchange. Dormancy is a feature of many plants of the temperate regions of the earth. Dormancy ensures that the seeds do not ripen at the time of dispersal which is generally late summer to autumn and then have the short cold days of winter to persevere. A successful strategy the plants have adopted is to be dormant through the trying days of winter and to reawaken with the warming spring. Plants are grouped into three lists Low temperature requirements, Light requirement and germination inhibitors
Low temperature. This is the requirement that the seed is subjected to a period of cold temperature to ensure germination or to speed up germination. For the horticulturalist it means seeds are placed in the refrigerator, usually at least one month. This is termed stratification. Seeds subjected to stratification generally germinate uniformly. Acaena Aciphylla Alseuosmia banksii Angelica Montana Aristotelia serrata Astelia Brachyglottis species Caystegia Carpodetus serrata Clematis Cordyline australis Corokia Cortaderia Cyathodes juniperina Dianell nigra Dodonea viscose Ealaeocarpus dentaus Entelea arborescens Fuchsia exorticata Gahnia Gaultheria Gresilnia littoralis Hebe species Hedycarya arborea Hoheria Leucopogon Libocedrus plumosa Lophomyrtus Macropiper excelsum Melicope simplex Melicytus ramiflorus Myoporum laetum Myrsine australis Nothofagus Olearia furfurace Phormium flax Phyllocladus trichomanoides Pittosporum species Podocarpus totara Prumnopitys Pseudopanax species Schefflera digitata Vitex lucens puriri Weinmannia racemosa
Light. It has been noticed that if soil or leaf litter is disturbed then a flush of germination by the seeds which were buried in the leaf litter or topsoil (termed the seed bank) may occur. Species which require light for germination are often opportunistic shrubs that may be found growing on disturbed soils. Seeds which suggest light is necessary for germination include: Acaena Agathis australis Carpodetus serratus Coprosma lucida Cordyline australis Geniostoma rupestre Hebe raoulli Hebe salicifolia Hebe speciosa Hedycarya arborea Hibiscus trionum Hoheria populnea Melicytus ramiflorus Metrosideros umbellata Olearia rani Pratia physaloides Schefflera digitata
Germination inhibitors. There are chemicals present in the testa or flesh of the fruit that need to be removed in order for germination to proceed. Wash the fruits or berries in water and physically remove the flesh. This is an adaptation that ensures that the seed does not germinate unless passed through the gut of a bird (and dispersed some distance from the parent plant), or the flesh has rotted away, which may be some time after seed dispersal. Generally a propagator of seeds will always remove the flesh of the fruit prior to sowing the seeds. Pseudopanax Melicytus ramiflorus Coprosma Cordyline
Scarification. In some species germination is quickened if the hard testa is nicked or cut with a scalpel or sharp knife prior to sowing. This allows water and oxygen to enter into the seed and will promote germination Sophora kowhai Clianthus kaka beak Carmichaelia NZ broom These are all members of the legume family.
References The Cultivation of New Zealand Trees and Shrubs L.J. Metcalf Reed 1991 The Cultivation of New Zealand Plants L. J. Metcalf Godwit 1993 Trees and Shrubs of New Zealand. A.L. Poole & N.M. Adams Government Print 1967 Plants of New Zealand Laing & Blackwell Whitcombe&Tombs 1964 New Zealand Native Shrubs and Climbers J. Smith- Dodsworth Bateman 1991 The Native Trees of New Zealand J.T. Salmon Reed 1982 Self incompatibility in Cordyline Pumilio N.Z, Journal of Botany 1983 Vol 21 : 93-95 R.E.Beaver The germination Ecology of Dysoxylum spectible N. Z. journal of Botany vol 26 1-6 1988 A.J. Court N. D. Mitchell Notes on Agathis australis C. T. Sando N. Z. journal of Forestry Vol 4 No 1 1936 Flower Biology in N.Z. E.J.Godley N.Z. Journal of Botany 1979 Vol 17 441-466 Breeding systems in N.Z. plants 5. Pseudowintera colorata ditto 1981 vol 19 151-156 E. J. Godley D.H. Smith Seed Biology of Chordospartium stevensonii L.N.and A.J. Conner ditto 1988 Vol 26 473-475 Seedling and shoot morphology of the N. Z. species of Nothofagus ditto Vol 26 401-407 W. R. Philipson Reproductive Biology of three species of Melicytus in N.Z. ditto 1984 vol22 81-94 Mary. H. Powlesland Flowering and fruiting patterns of three species of Melicytus in N.Z. 1985 vol 23 581-596 M.H. Powlesland, M Philipp, D.G. Lloyd. The soil seed bank of a Kauri forest remnant, near Auckland. N.Z. journal of Bot. vol26 no.2 1988 223-236 N.J. Enright E.K. Cameron Environmental factors controlling germination of Leptospermum scoparium (Manuka). N.Z. Journal of Botany 1984 vol 22: 95-101. E. Mohan. N. Mitchell. P. Lovell. genetic Variation in Rimu - an investigation using isozyme analysis. N.Z. Journal of Botany 1989 Vol 27: 83-90. B.J. Hawkins. G.B. Sweet. Breeding Systems in N.Z. plants 5. Pseudowintera colorata (Winteraceae) N.Z. Journal of Botany 1981 Vol 19 151-156.E.J. Godley and Diane H.Smith. Don't Keep off the grasses. Commercial Horticulture, November 1989. The Fruit of Vitex lucens (verbenaceae) E.J. Godley N.Z. Journal of Botany December 1971. Seed germination of five subalpine Acaena species N. Z. Journal of Botany 1987 Vol 25:1-4. L.N. Conner. Reproductive Biology of Phormium tenax: a honey eater- pollinated species. N.Z.Journal of Botany 1988 vol 26: 453-463. J.L. Craig. A. M, Stewart. Narrow leaved snow tussock N.Z. Journal of Botany Sept 1965. Mark. The ecology of Dacrydium cupressinum: a review N.Z. Journal of Botany, 1988 Vol26: 37-62. D.A. Norton J.W.Herbert A.E.Beveridge. Paths to maturity E.J.Godley N.Z. Journal of Botany 1985 Vol 23: 687-706. Flower Biology in New Zealand E.J. Godley N.Z. Journal of Botany 1979 Vol. 17 441-466 Germination requirements of New Zealand plants: a review D.W. Fountain, H.A. Outred N.Z. Journal of Botany 1991 Vol 29 311-316 Volatiles from ripe fruits of Karaka (cornyocarpus laevigatus) D.W. Fountain K. Couchman n.z. journal of Botany 1984 Vol 22: 341-343. Seed germination in Gaultheria antipoda, G. depressa, and Pernettya macrostigma. P. Bannister.Nz Journal of Botany 28(3), 1990 A buried seed experiment using caryopses of Chionocloa macra, South Island NZ J.R. spence. Seeds, seedripening, Germination and viability in some species of Hebe M.J.A. Simpson Proceedings of the New Zealand Ecological Society, Vol 23 1976. Responses of seeds to three species of Pseudopanax to low temperature stratification, removal of the fruit flesh, and application of gibberellic acid. P. Bannister, J. Bridgeman NZ Journal of Botany, 1991 Vol 29:213-216. Germination of Miro ( Prumnopitys ferruginea) seeds after consumption by NZ pigeons (Hemiphaga novaeseelandia). M.N. Clout, J.A.V.Tilley NZ Journal of Botany 1992 Vol 30: 25-28. A germination inhibitor in the seeds of Mahoe (Melicytus ramiflorus) T.R. partridge M.D. Wilson NZ Journal of Botany 1990, Vol 28: 475-478 The dispersal unit of Dacrycarpus dacrydioides and the significance of the fleshy receptacle.D.W. Fountain, J.M. Holdsworth, H. A. Outred Botanical Journal of the Linnean Society 1989, 99 197-207 Soil Seed Banks of secondary vegetation on the port hills and Banks peninsula, Canterbury, NZ., and their role in succession. T.R. Partridge NZ Journal of Botany, 1989, Vol 27; 421-436 The role of lizards in NZ plant reproductive strategies.A.H. Whitaker NZ Journal of Botany, 1987, Vol 25 : 315-328 Patterns of delayed germination in seeds C.J. Burrows NZ Natural Sciences 16(1989). Germination and Dormancy of Artropodium cirratum seeds. A. J. Conner and L.N. Conner N.Z. Natural Sciences 15 (1988) Lack of dormancy in seeds of NZ plants M. J. A. Simpson Journal of the Canterbury Botanical Society. Vol 13
| New Zealand Ferns and Allied Plants There is nothing more evocative of New Zealand "bush" than ferns, from tall tree ferns to epiphytes and species which sprawl over the ground or nestle in the dim light of crevices. This volume covers some 184 species plus the 22 related plants known as "fern allies" to enable ready identification. | | Growing Gardens for Free: A Plant Propagation Guide for New ZealandEveryone can grow plants for free and this informative book shows how to propagate over 1000 common plants, with specific detailed instructions on over 500 of the world's most popular ornamental plants. The book is illustrated with both practical step-by-step photographs of propagation techniques and the plants themselves. There are also extensive tables covering 1000 plants with information on which propagation technique to use - seed, cuttings, grafting, division - and then details of temperature requirements, time to germination/strike, % strike rate and time of year to propagate. The information has been gleaned by the author from over 25 years as a propagator and hybridiser, specialising in ornamental shrubs, such as rhododendrons and azaleas. He shares this knowledge through a clear and concise text. | | Growing New Zealand Plants, Shrubs and Trees A completely revised and updated version of Muriel Fisher's original text first published in 1970. Changes in garden styles and nomenclature have necessitated the revision, as has the increased knowledge and sophisitication of New Zealand gardeners. It includes over 120 photographs. |
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