Tree Seed Sowing Information

This is a guide only as it is difficult to accurately state when a tree seed will germinate, do not discard trays too early, they may germinate the following year. NOTE when per-chilling, open the sealed bags to allow air to enter twice weekly. You may notice seed germinating while in the fridge, remove and sow this seed. Seed requiring Pre treatment (stratification) can be either sown in pots and left outside for nature to take its course (ensure pots are covered to prevent mice eating the seeds) or it can be mixed with a small amount of damp vermiculite, damp sand or damp sphagnum moss and sealed in a plastic bag and then placed in the fridge for the stated time.  For the longer stratification requirements of some species it may be practical to sow outdoors where they will be exposed to the normal seasonal temperature fluctuations e.g. those labeled DD.  Seed labelled DD50 should be sown in April if the germination is required the following spring, this would give the seed 20 weeks of warm stratification (summer) followed by 30 weeks cold stratification (winter). After Pre-treatment seed requires sowing, Fine seed sow on compost surface larger seed cover, sow in either pots, trays or plugs/cells. Please note some species may take a couple of years to germinate.

KEY to code found on seed packet label.  Pre-treatment to be applied prior to sowing the seed.

 L         Pour several lots of  hot water (not boiling) over the seeds or rub seed on sandpaper to break down the  seed coating, leave the seeds to soak for 5-10 hours until seed coating has softened and seed swollen slightly if no swelling takes place (seed does not imbibe water) continue soaking or break down outer seed surface and then soak, Continue treatment until 75%+ of  seeds imbibe water. then sow seed at 18° C +

LW     Wisteria seed soak in warm water for 4 hours and then sow at 20° C +

SD  These seeds will benefit from a moist pre chilling treatment. Use the same technique as code PC below

 PC      These seeds are not actually dormant, but will germinate faster if given a moist chilling (or pre-chilling) at 0-2° C for up to 10 weeks.

Pre soak seed for 24-48 hours drain and place in polythene bag or container and tie while still moist place in fridge, keep mixed regularly during cold storage, store for the time indicated on label or minimum 4 weeks. Then sow seed at 18° C +

ND or  O    No pre-treatment required, sow at 18° C +

 MD   These seeds will not germinate at all unless given a lengthy period of chilling. Soak seed in running water for 48 hours, drain and mix with sieved peat and sharp sand or vermiculite. (Mix with equal volume of sieved peat and sharp sand mist sprayed to dampen do not get the medium too wet or seed will rot).  Place in polythene bag tie lightly, store for the number of weeks indicated on the label for that species, e.g. MD14 = 14 weeks chilling, some seed will require warm stratification first this will be indicated on the label

 e.g. MD16; 2 weeks at 16-20° C followed by 14 weeks cold strat (pre chilling).  Tree Seed often has more even germination if kept for 2 weeks at 18-20° C prior to chilling period.

Mix the seed twice a week in the bag to allow fresh air to enter and the seed to breathe.

 DD   These seeds are deeply dormant and require a lengthy period under warm and cold conditions. Natural temperature fluctuations are the most effective i.e. sow outdoors and allow nature to take its course.

Mix with equal volume of sieved peat and sharp sand mist sprayed to dampen do not get the medium too wet or seed will rot. Soak seed in running water for 48 hours, drain and mix with sieved peat and sharp sand.  The conditions can be given artificially by using a warm room and refrigerator. Dry seed often has more even germination if kept for 2 weeks at 18-20° C.    Treat the seed for the number of weeks indicated for the species. Mix the seed twice a week in the bag to allow fresh air to enter and the seed to breathe.

Monkey Puzzle Tree Pre treated Seed when available   (Araucaria araucana) BZ036

Germinated  seeds  Pot up on receipt into 9cm  pots of gritty compost with added pearlite either lay seed on surface & lightly cover root radical,  Or can be inserted sprouted part (root radical) fully into compost leaving 1/3 of seed above compost. Grow on outdoors but protect seedlings during very cold weather ( & from squirrels mice etc) or in greenhouse. Due to the warm climate of these trees growing on in greenhouse/indoors is the preferred method.

Pre-Treated Seeds

Recommended compost 70% moss peat or well rotted garden compost 20% medium grit or pearlite 10% loam and slow release fertiliser,  this compost is suitable for all the tree seeds. The seed has been subject to a cold period of 6 to 18 months and are ready to sow on receipt some seeds will have already have germinated. For the best results from these seeds  place in bottom of refrigerator on receipt until end of March (if receiving them early winter onwards), check seed weekly to see if any have started to germinate, if so, sow the seed in a frost free place. Sprinkle seed over the surface of the compost, keep compost just moist (too much water can rot the seedlings) germination may take several months, please note not all the seed will germinate and it is advisable not to discard the seed for a couple of years. Seed from Acer palmatum may not always come true to the parent tree, many will produce a range of variable seedlings, many may be unique.

Tree seed sowing codes

Abies Concolour White fir SD
Abies Fraseri Fraser fir SD
Abies Grandis Giant Fir SD
Abies Nobilis   (procera)  Noble fir  [Wales Blue Strain] SD
Abies Nordmanniana  Nordmann fir SD
Abrus praecatorius Crabs eye   Jumbie beads L
Acacia baileyana Cootamundra Wattle L
Acacia dealbata Silver Wattle  L
Acacia Decurrens Early Black Wattle L
Acacia podaluriifolia   Queensland Silver Wattle L
Acer campestre Field Maple DD34
Acer Cappadocium  Caucasian Maple DD28
Acer Capillipies Red Snake Bark Maple DD28
Acer circinatum Vine Maple DD28
Acer davidii Snakebark Maple  MD12
Acer ginnala Amur Maple DD34
Acer ginnala Flame Flame Maple DD28
Acer griseum Paper-bark Maple DD50
Acer griseum Stratified Paper-bark Maple  
Acer Henryi   MD12
Acer Japonicum Full moon maple DD28
Acer Japonicum aconitifolium Fern leaf maple DD28
Acer Macrophyllum Oregon Maple DD28
Acer monspessulanum Montpellier Maple DD28
Acer Negundo Box Elder MD20
Acer Nikoense  Nikko Maple DD50
Acer Palmatum Japanese Maple DD34
Acer Palmatum ssp Palmatum Japanese Maple small leaf form MD20
Acer Palmatum Dissectum Japanese maple MD20
Acer Palmatum Dissectum Viridis Gree fern leaf Maple MD20
Acer Palmatum Elegans   MD20
Acer Palmatum Hessei Heptolobum  Elegans Purpureum MD20
Acer Palmatum Korean Gem   MD20
Acer palmatum osakazuki Japanese Maple MD20
Acer palmatum siegen Japanese red maple MD20
Acer Palmatum Tana   MD20
Acer palmatum atropurpureu Blood Leaf Japanese Maple DD34
Acer platanoides Norway Maple MD12
Acer pseudosieboldianum Korean Maple MD12
Acer pseudoplatanus Great Maple  Sycamore Maple MD12
Acer saccharinum Silver Maple Not Dormant
Acer saccharum Sugar Maple MD12/DD24
Acer buergerianum Trident Maple DD34
Acer rubrum Red Maple MD12
Acer Rufinerve Snake Bark maple  MD20
Acer Sieboldianum   MD20
Acer Triflorum Rough Barked Maple DD28
Acer truncatum Shantung maple MD12
Actinidia kolomikta   VAR10
Adansonia digitata Baobab 0
Ailanthus Altissima Tree of Heaven PC3-10
Akebia quinata Chocolate Vine PC10
Akebia trifoliata   PC10
Albizzia julibrissin Silk Tree L
Alnus cordata  Italian Alder PC6
Antigonon leptopus Coral vine or Mexican creeper O
Aralia Spinosa Hercules Club  Devils Walking Stick Cold Germinater
Arctostaphylos uva-ursi Bearberry  Common  DD28
Araucaria araucana  Monkey Puzzle Not Dormant
Arbutus Unedo Strawberry Tree PC3-10
Argyreia nervosa Wooly Morning Glory O
Asimina triloba pawpaw does not keep MD12-14
Betula Pendula  UK 403 Silver Birch PC10
Betula nigra River Birch PC6
Betula Utilis Himalayan Birch PC6
Betula papyrifera Paper Birch PC6
Brachychiton rupestris Australian Bottle Tree L
Camellia japonica Camellia MD12
Caragana Arborescens Siberian Pea Shrub L
Carica Papaya Papaya  Pawpaw O
Catalpa Bignonoides Indian Bean Tree ND
Cedrus Atlantica Atlas Cedar SD
Cedrus Deodara Indian Cedar SD
Cedrus libani Cedar of Lebanon SD
Celtis australis Southern Nettle Tree MD12
Ceratonia  siliqua  Locust /Carob tree L
Cercis Canadensis Eastern Redbud L
Cercis Siliquastrum Judas Tree L
Carpinus betulus Hornbeam Common DD39
Chaenomeles Largenaria Japanese flowering Quince MD18
Chaenomeles Japonica Japanese Quince  Dwarf Quince MD18
Chamaecyparis Lawsonia Lawson Cypress PC
Cinnamomum camphora Camphor tree O
Cornus alba sibirica Dogwood MD14
Corylus avellana Hazel       MD16
Corylus colurna Turkish Hazel MD16
Cotoneaster horizontalis Rockspray Cottoneaster DD39
Cupressus cashmeriana Kashmir Cypress PC 4-6
Cupressus macrocarpa Monterey Cypress PC4
Cryptomeria japonica Japanese Cedar PC4
Ecremocarpus scaber Chilean Glory Vine 0
Elaeagnus angustifolia Oleaster MD12
Erythrina crista galli Coral Tree O
Fagus Sylvatica Beech MD12
Fagus Sylvatica atropurpureum Beech  
Ficus benghaldensis Banyan  Indian Fig O
Ficus benjamina Weeping Fig O
Ficus macrophylla Australian Banyan O
Ficus rubiginosa Port Jackson Fig O
Fraxinus Excellsior Ash DD34
Fraxinus Ornus Manna Ash DD34
Ginko  Biloba Maidenhair tree Not Dormant
Gleditsia Triacanthos Honey Locust L
Hamamelis  japonica Japanese Witch Hazel    DD34
Hamamelis  virginiana Common Witch Hazel  DD34
Jasminum nudiflorum Winter Jasmine MD12
Juglans Nigra Black Walnut MD16
Juglans Regia Walnut MD16
Juniperus chinensis Chinese Juniper MD14
Juniperus communis Juniper DD36
Juniperus rigida Needle Juniper MD14
Koelreuteria paniculata Pride of India Scarify + MD14
Laburnum alpinum Scotch Laburnum L
Laburnum anagroides Laburnum Common L
Larix leptolepis Japanese larch PC4-6
Libocedrus decurrens Incense Cedar PC6
Ligustrum vulgare Privet MD16
Liquidambor styraciflua Sweet Gum PC8
Lycium chinensis Chinese Wolfberry  Chinese Boxthorn  Not Dormant
Magnolia Kobus        Japanese Magnolia DD25
Magnolia liliflora Mu-lin DD25
Magnolia soulangiana Saucer Magnolia DD25
Magnolia grandiflora Bull Bay MD12
Malus baccata  Siberian Crab Apple MD16
Metasequoia glyprostroboides Dawn Redwood PC4
Moringa oleifera Horseradish-tree O
Morus Alba White Mulberry MD16
Morus nigra Black Mulberry  MD16
Mucuna albertisii Hamburger Bean  Sea Bean L
Mucuna deringiana Velvet Bean L
Myristica Fagrans Nutmeg O
Nothofagus Antarctica Antarctic Beech PC10
Olea europea Olive  DD34
Parthenocissus tricuspidata Boston Ivy MD12
Parthenocissus veitchii Boston Ivy     Autumn purple leaved MD12
Phellodendron amurensis Amur Cork Tree MD12
Picea Abies   SOW DIRECT
Picea englemannii Englemann Spruce PC4
Picea glauca White spruce PC4
Picea Omorika Serbian Spruce PC
Picea Pungens Glauca Blue Spruce PC
Pinus mugo-mughus Mountain Pine PC6
Pinus thunbergii Japanese black pine PC6
Pinus densiflora Japanese red pine PC4
Pinus parviflora Japanese white pine DD36
Pinus Parviflora Brevifolia Japanese white pine DD36
Pinus halepensis  Aleppo pine PC4
Pinus sylvestris Scottish pine PC4
Prunus avium Wild Cherry DD29
Prunus Mahaleb St Lucie Cherry DD29
Prunus Mume Japanese Apricot MD20
Prunus spinosa Sloe DD29
Prunus Serrulata Japanese Flowering Cherry MD20
Pseudotsuga taxifolia Douglas fir PC
Punica Granatum Pomegranate MD14
Punica granatum nana Dwarf Pomegranate MD14
Pyrus Communis Common Pear MD16
Quercus Ilex Holm Oak SOW DIRECT
Quercus  Robur  UK403 English Oak SOW DIRECT
Quercus Rubra Red Oak SOW DIRECT
Quercus cerris Turkey Oak SOW DIRECT
Robina pseudoacacia False Acacia/Black Locust L
Rosa (All)

Samanea Samen
Scarification reduces stratification time

Monkey Pod Rain Tree

Sambucus racemosa Elder red beried DD39
Sapium sebiferum Chinese Tallow Tree MD10
Sciadopitys verticillata Japanese Umbrella Pine DD36 to PC20
Sequoiadendron giganteum Giant Redwood/Big tree PC9
Sequoia Sempervirens   PC9
Sophora Japonica Japanese Pagoda Tree L
Sorbus Aucuparia Mountain Ash Rowan MD16
Spathodea campanulata African Flame Tree O
Styrax Japonica Snowbell MD16
Syringa Vulgaris Common Lilac MD16
Taxus Baccata Yew DD70 
Tilia Cordata Lime small leaved DD39
Thuja compacta orientalis v pyramidalis Chinese Arbor-vitae PC8
Tsuga Heterophylla Western Hemlock PC
Ulmus glabra Wych elm Not Dormant
Ulmus parviflora Chinese Elm  Not Dormant
Vaccinium myrtillus Bilberry MD12
Wisteria sinensis blue Chinese Wisteria Not Dormant
Wisteria floribunda Japanese Wisteria LW
Zelkova serrata Japanese Zelkova PC6
Zelkova carpinifolia Caucasian Elm PC6
Zizyphus Jujuba Chinese Date MD12



Scarification :- The germination of some seeds is greatly improved by rubbing the seeds lightly between two sheets of sandpaper or soaking in water to break down the hard coating which prevents the seed from imbibing moisture.

Stratification :- Tree seeds have to be subjected to a period of cold and warm stratification to break their dormancy before germination takes place, as it would normally in the spring. You can provide the period of cold by adding the seed to damp sieved peat, sand or vermiculite and putting it in a plastic bag in the fridge for 2-32 weeks dependant on species.