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It is moderately [[serotiny|serotinous]], storing only one-tenth the number of seeds in its seed bank as the reseeding ''B. hookeriana'' with which it coexists on sand dunes in scrub at [[Eneabba, Western Australia|Eneabba]] north of Perth. Even then, many of its follicles do not release seed after a fire, but instead after successive autumn rains.<ref>{{cite journal |author1=Enright, N.J. |author2=Lamont, B.B. |year=1989 |title=Seed banks, fire season, safe sites and seedling recruitment in five co-occurring ''Banksia'' species |journal=Journal of Ecology |volume=77 |issue=4 |pages=1111–22 |jstor=2260826 |doi=10.2307/2260826}} {{subscription required}}</ref> An experiment simulating wet weather following a fire saw a series of ''Banksia attenuata'' cones with follicles subjected to twice-weekly immersions in water after being heated in a ring [[Bunsen burner|Bunsen]] flame to around {{convert|500|–|600|C|F}} for two minutes. Cones that had been exposed to water for more weeks had more seed released from follicles over time; around 40% released at three weeks, increasing steadily to almost 90% at ten weeks, compared with a series of [[scientific control|controls]] (which were kept dry) of which fewer than 10% of seed released. Thus, the seed remains in the follicles until successive rains result in seed dispersal in the wetter winter (instead of dryer summer), increasing the chance of survival. After the follicle is split, the seed and [[seed separator|separator]] are exposed to the elements. The wings of the woody separator are [[hygroscopic]], move together when wet, and spread and curl apart when dry. The seed is gradually drawn out by the movement with each wetting.<ref>{{cite journal|last1=Cowling |year=1985|title=Seed release in ''Banksia'': the role of wet-dry cycles|journal=Australian Journal of Ecology |volume=10 |issue=2 |pages=169–71 |doi=10.1111/j.1442-9993.1985.tb00878.x|first1=Richard M.|last2=Lamont|first2=Byron B.}}</ref>
Once released, seed germinates at temperatures between {{convert|15|and(-)|20|C|F}} to optimise timing with autumn and winter rains and hence maximise chance of survival. Still, many seedlings die off in the hot and dry summer months.<ref>{{cite journal|last1=Cowling |year=1985 |title=Post-fire recruitment of four co-occurring ''Banksia'' species |journal=Journal of Applied Ecology |volume=24 |issue=2 |pages=645–58 |jstor=2403899 | doi = 10.2307/2403899|first1=R. M. |last2=Lamont |first2=B. B.}} {{subscription required}}</ref> Seedling survival for the species is lower than for banksias which regenerate by seeding over time. Despite this, the longevity of mature plants allows for maintenance of population until favourable years enable better survival of young plants. As they mature, plants are less likely to perish and are estimated to live for 300 years or more.<ref>{{cite journal |author1=Enright, N. J. |author2=Lamont, B. B. |title= Recruitment variability in the resprouting shrub ''Banksia attenuata'' and non-sprouting congeners in the northern sandplain heaths of southwestern Australia| journal=Acta Oecologica |volume=13 |issue=6|pages=727–41|year=1992}}</ref> Analyzing the seed bank and longitudinal results over fifteen years on the Eneabba sandplain showed that ''B. attenuata'' would become more abundant over time with fire intervals averaging between 6 and 20 years, peaking with intervals around 10 to 12 years, compared with longer intervals for the reseeders ''B. hookeriana'' and ''B. prionotes''. Placed against its rivals, ''B. attenuata'' would be dominant between 8 and 10 or 11 years, but at longer intervals is outcompeted by ''B. hookeriana''. Variability in the timing between fires allows all three species to coexist. Exaggerated good and bad weather conditions favours ''B. attenuata'' over the reseeding species, which suffer more.<ref name="Groeneveld 2002">{{cite journal |last1=Groeneveld |first1=J. |last2=Enright |first2=N.J. |last3=Lamont |first3=B.B. |last4=Wissel |first4=C. |year=2002 |title=A spatial model of coexistence among three ''Banksia'' species along a topographic gradient in fire-prone shrublands |journal=Journal of Ecology |volume=90 |issue=5 |pages=762–74 |doi=10.1046/j.1365-2745.2002.00712.x |jstor=3072246|doi-access=free }} {{subscription required}}</ref>
Despite having relatively heavy seed, seed from ''Banksia attenuata'' has a high rate of long-distance dispersal. A genetic study of populations in Eneabba showed that over 5% of plants had originated up to {{convert|2.6|km|mi|abbr=on}} away (similar rates to ''Banksia hookeriana'', the seed of which only weighs half as much). The mechanism for this is unclear, although [[Byron Lamont]] has proposed the [[Carnaby's black cockatoo]] (''Zanda latirostris'') as a [[dispersal vector|vector]]; the species seeks out ''Banksia attenuata'' cones after bushfire, possibly because the large seeds and greater chance of grubs in the cone make them more nutritious.<ref>{{cite journal|title=Long-distance dispersal of seeds in the fire-tolerant shrub ''Banksia attenuata''|author1=He, Tianhua |author2=Lamont, Byron B. |author3=Krauss, Siegfried L. |author4=Enright, Neal J. |author5=Miller Ben P. |journal=Ecography| volume=32 |issue=4 |pages=571–80 |year=2009 |doi=10.1111/j.1600-0587.2008.05689.x}}</ref> Flowering has been recorded one to two years after a bushfire.<ref name=atlas />
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