Temperature and sunlight are more important growth parameters than nutrient concentrations. Duckweed grows across a wide temperature range – between 6oC and 33oC – but we’ve determined that it grows best in a range of 18oC to 24oC.n the right conditions, this tiny plant can double its mass every 24 – 48 hours. Close control of the production parameters for duckweed is relatively easy in the small ponds and tanks favoured by backyard food producers.