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The second aspect of Brettanomyces cell growth is that it typically takes about 7-8 days to reach it's maximum growth <ref>[http://www.brettanomycesproject.com/dissertation/propagation-and-batch-culture-growth/propagation-results/ Yakobson, Chad. The Brettanomyces Project. Propagation and Batch Culture Results. Retrieved 2/17/2015]</ref>. Thus, each step of a starter for Brett should be 7-8 days.
A Brett starter strength and size can be accurately calculated using an online yeast calculator such as [http://www.mrmalty.com/calc/calc.html Mr. Malty] or [http://yeastcalculator.com/ YeastCalc] using the 'hybrid' yeast type setting. This will calculate a pitching rate somewhere between ale and lager pitching rates, which should be adequate for 100% Brettanomyces fermentations. Maintaining a temperature of 70°-80°F/20°-26°C should be adequate for most strains. After the 7-8 days of growth, the entire starter should be pitched into the fermenter (Brettanomyces is known for not flocculating well, even if cold crashed). Cold crashing will also slow the metabolism of Brett. Therefore cold crashing is generally not advisable.
It is worth noting that a "Malt Yeast Peptone Glucose" growth substrate has been shown to be a better substrate for growing an initial pitch of Brettanomyces. Specifically, when grown in wort, Brettanomyces will go through a 24 hour lag phase, a growth phase, another lag phase, and a second growth phase (all within 7-8 days). When grown in MYPG substrate, there is only a single growth phase and no lag phase, which has been reported by Yakobson to produce a larger cell count in the same amount of time <ref>[http://www.brettanomycesproject.com/2009/08/mypg-vs-wort-as-the-growth-substrate/ Yakobson, Chad. The Brettanomyces Project. MYPG Compared to Wort as a Growth Substrate. Retrieved 2/18/2015.]</ref>. Cells grown in MYPG also are better adapted to grow in wort <ref>[http://www.brettanomycesproject.com/dissertation/propagation-and-batch-culture-growth/propagation-discussion/ Yakobson, Chad. The Brettanomyces Project. Propagation and Batch Culture Discussion. Paragraph 5. Retrieved 2/18/2015.]</ref>. Practical instructions for making this substrate can be found on Jason Rodriguez's blog, "[http://sciencebrewer.com/2011/04/29/wild-yeast-project-mypg-culture-media/ Brew Science - Homebrew Blog]".