Temperature impacts cactus and succulent development rate

One cactus and 17 succulent species/cultivars were grown at 10, 16, 22, or 28 °C (plant temperature) for 10 or 15 weeks. The change in leaf/tubercle number at each temperature (after 10 or 15 weeks) was determined, and leaf/ tubercle-unfolding rate was calculated. ‘Jade Necklace’ kebab bush (Crassula rupestris ssp. marnieriana), ‘Lola’ echeveria (Echeveria), ‘Green Ice’ gasteraloe (Gasteraloe), and lithops (Lithops species) leaf-unfolding rate per day was unaffected by temperature. Leaf-unfolding rate per day increased as temperature increased from 10 to 16 °C on ‘Firebird’ aloe (Aloe), ‘Key Lime Pie’ adromischus (Adromischus cristatus), prostate rainbow bush (Portulacaria afra variegata), burro’s tail (Sedum burrito), and ‘Sir William Lawrence’ houseleek (Sempervivum calcareum). Leaf-unfolding rate per day increased as temperature increased from 10 to 22 °Con mescal agave (Agave parryi truncata), ‘Firebird’ aloe, Sunrise anacampseros (Anacampseros telephiastrum variegata), ponytail palm (Beaucarnea recurvata), subsessilis echeveria (Echeveria subsessilis), zebra plant (Haworthia fasciata), prostrate rainbow bush, burro’s tail and ‘Sir William Lawrence’ houseleek. Increasing temperature from 22 to 28 °C decreased ‘Kiwi’ tree houseleek (Aeonium percarneum) leaf-unfolding rate per day, increased ‘Firebird’ aloe and tiger tooth aloe (Aloe juvenna) leaf-unfolding rate, and resulted in shoot tip death on burro’s tail, and plant death of ‘Sir William Lawrence’ houseleek and ‘Silver Dollar’ jade (Crassula arborescens). The cactus, ‘Arizona Snowcap’ mammillaria (Mammillaria gracilis fragilis), tubercle-unfolding rate per day increased as temperature increased from 16 to 28 °C. Taken together, temperature (10 to 28 °C) effects on development rate were species specific and related to the indigenous environment of a species.