How to Smoke Treat Seeds

How to Smoke Treat Seeds to Improve Germination

“Smoke treatment” or “Seed smoke treatment” refers to the practice of encouraging improved germination rates by applying organic smoke, or smoke-infused preparations, to seeds. This may be done either prior to or at planting and – for some species – can also induce improved root mass and other benefits.

This technique has proved especially useful with regard to the germination of more difficult seed, particularly those which generally germinate naturally after intense bushfires and the like. Many such species originate from exceedingly hot regions of Australia and South Africa, an example of which is the tree Acacia mearnsii (the ‘Black Wattle).

With that in mind, it’s good to remember that plants which benefit from smoke treatment often share this proclivity with others of their genus, so it’s always worth experimenting, should you think it potentially worthwhile. Incomplete lists of species and genera known to benefit from seed smoke treatment appear further down the page, after the tutorial.

So, read on for the how-to – don’t forget to always check weather conditions and the surrounding area for possible hazards (children, flammable material, etc.) before starting any fires!

How to smoke treat seeds to improve germination

How to Smoke Treat Seeds – Materials

  • Australian native seeds (e.g. Acacia species)
  • Barbecue kettle (with lid)
  • Dried leaves
  • Grill plate(s)
  • Lighter (or matches, etc.)
  • Mixing bowl
  • Plastic container (e.g. a takeaway container)
  • Straw
  • Bellows or fan (optional)

How to Smoke Treat Seeds – Method

  1. Mix up a few handfuls of the leaves and straw (do not use wood!) in the mixing bowl.
  2. Transfer the mixed leaves and straw to the bottom of the kettle, placing them to one side.
  3. Light the dried material, using your breath or hands, etc. to encourage the flames. Get it nice and smoky!
  4. Carefully, sprinkle the seeds in a fine and even layer into the plastic container.
  5. Place the grill plate(s) over the of the fire and then, on the opposite side from the flames, put the seed container on top.
  6. Put the lid on the kettle and wait a few minutes, monitoring the situation all the while.
  7. Lift up the lid and check the seeds every few minutes to ensure the embers remain smouldering. If the container starts to melt at any point, the kettle is too hot!
  8. Leave the seeds to smoke for roughly twenty to thirty minutes, after which time you can remove the container from the kettle and allow everything to cool down. Put the fire out with some water, or cover it with dirt.
  9. Presuming you’ve followed the instructions, your seeds should now be coated with a light-brown coat which contains the beneficial chemicals (including cyanohydrin and karrikinolide) from the smoke.
  10. Set the seeds aside to dry and sow into pre-watered soil (to prevent washing the chemicals away before they have a chance to take effect) within twelve months.

Some Species Which Benefit from Smoke Treatment

  • Acacia caven (‘Espinillo’)
  • Acacia cyclops (‘Coastal Wattle’)
  • Acacia hebeclada (‘Candle Thorn’)
  • Acacia mearnsii (‘Black Wattle’)
  • Acacia robusta
  • Achnatherum hymenoides (‘Indian Ricegrass’)
  • Achnatherum occidentalis (‘Sierra Nevada Needlegrass’)
  • Achnatherum thurberianum (‘Thurber’s Needlegrass’)
  • Alcea pallida
  • Alyssum fulvescens
  • Allophyllum glutinosum
  • Antirrhinum coulterianum
  • Antirrhinum kelloggii
  • Antirrhinum nuttallianum
  • Aotus ericoides ‘Common Aotus’
  • Audounia capita
  • Avena barbata
  • Calytrix leschenaultii
  • Camissonia californica
  • Capsella bursa-pastoris
  • Caulanthus heterophyllus
  • Chaenactis artemisiifolia
  • Cistus creticus
  • Cistus salviifolius
  • Corymbia maculata
  • Crepis foetida
  • Cryptantha clevelandi
  • Cryptantha micrantha
  • Daucus carota (‘Carrot’)
  • Emmenanthe penduliflora
  • Erica sessiliflora
  • Eucrypta chrysanthemifolia
  • Festuca idahoensis (‘Idaho Fescue’)
  • Helianthemum salicifolium
  • Hesperostipa comata (‘Needle-and-thread’)
  • Isatis tinctoria
  • Lechenaultia biloba
  • Mentzelia micrantha
  • Mimulus clevelandii
  • Onopordum caricum
  • Penstemon centranthifolius
  • Phacelia grandiflora
  • Phacelia minor
  • Phleum exaratum
  • Purshia tridentata (‘Antelope Bitterbrush’)
  • Romneya coulteri
  • Rumex tuberosus
  • Salvia apiana (‘White Sage’)
  • Salvia columbariae
  • Salvia leucophylla
  • Salvia mellifera
  • Sanguisorba minor
  • Silene behen
  • Silene multinervia
  • Silene vulgaris
  • Stachys cretica
  • Thymbra spicata
  • Torilis leptophylla
  • Tragopogon longirostis

Genera Containing Species Which Benefit from Smoke Treatment

  • Acacia
  • Acanthocarpus
  • Acrotriche
  • Actinostrobus
  • Actinotus
  • Adenanthos
  • Agonis
  • Agrostocrinum
  • Allocasuarina
  • Alyxia
  • Amphipogon
  • Andersonia
  • Anigozanthos
  • Arthropodium
  • Astartea
  • Astroloma
  • Baeckea
  • Banksia
  • Billardiera
  • Blancoa
  • Boronia
  • Bossiaea
  • Brunonia
  • Burchardia
  • Bursaria
  • Caesia
  • Callitris
  • Calytrix
  • Chamaescilla
  • Chieranthera
  • Clematis
  • Codonocarpus
  • Comesperma
  • Conospermum
  • Conostephium
  • Conostylis
  • Crassula
  • Cryptandra
  • Cyathochaeta
  • Dampiera
  • Desmocladus
  • Dianella
  • Diplolaena
  • Drosera
  • Epacris
  • Eriostemon
  • Eucalyptus
  • Exocarpus
  • Gahnia
  • Geleznowia
  • Georgiella
  • Gompholobium
  • Gonocarpus
  • Grevillea
  • Gyrostemon
  • Haemodorum
  • Hakea
  • Hemigenia
  • Hemiphora
  • Hibbertia
  • Hovea
  • Hyalosperma
  • Hybanthus
  • Hybantyhus
  • Hydrocotyle
  • Hypocalymma
  • Isopogon
  • Isotoma
  • Johnsonia
  • Kennedia
  • Lachnostachys
  • Lasiopetalum
  • Laxmannia
  • Lechenaultia
  • Leptomeria
  • Leptospermum
  • Leucopogon
  • Levenhookia
  • Lobelia
  • Lomandra
  • Loxocarya
  • Lysinema
  • Macropidia
  • Melaleuca
  • Mitrasacme
  • Myriocephalus
  • Neurachne
  • Opercularia
  • Orthrosanthus
  • Patersonia
  • Persoonia
  • Petrophile
  • Phyllanthus
  • Picris
  • Pimelea
  • Pityrodia
  • Platysace
  • Pomaderris
  • Poranthera
  • Ptilotus
  • Ricinocarpus
  • Rulingia
  • Scaevola
  • Siegfriedia
  • Sollya
  • Sowerbaea
  • Sphenotoma
  • Spyridium
  • Stackhousia
  • Stipa
  • Stirlingia
  • Stylidium
  • Taraxacum
  • Tersonia
  • Tetraria
  • Tetrarrhena
  • Tetratheca
  • Thysanotus
  • Trachymene
  • Trichocline
  • Tripterococcus
  • Trymalium
  • Velleia
  • Verticordia
  • Waitzia
  • Xanthorrhoea
  • Xanthosia