Phenology of selected Rutaceae collections at Purwodadi Botanic Garden in East Java, Indonesia

Plants change their vegetative and reproductive activities as a mechanism to adapt to climate change. This study aimed to document the flushing, flowering and fruiting patterns of 16 Rutaceae species grown at Purwodadi Botanic Garden, East Java. Observations were conducted fortnightly for four years, covering abundances of leaves, flowers and fruits, and used a scoring method from 0–4. The results showed two species with differences in their vegetative activities. Murraya koenigii (L.) Spreng. and Zanthoxylum rethsa DC shed their leaves to a class of 2 (50%). The observed flowering and fruiting patterns included frequency (continual, sub-annual, annual and supra-annual) and class (regular and irregular). The observed species fell into four different frequencies of flowering patterns: annual (nine species), sub-annual (two species), continual (four species) and supra-annual patterns (one species). Most of the observed species performed flowering patterns that differ from their fruiting patterns. Seven species showed same flowering and fruiting patterns, namely Clausena lansium (Lour.) Skeels, Euodia suaveolens var. ridleyi, Glycosmis pentaphylla (Retz.) DC., Luvunga sarmentosa Kurz., Micromelun minutum Wight & Arn., Murraya paniculata (L.) Jack and Triphasia trifolia (Burm.f.) P.Wilson. Some species belonging to regular class performed same flowering time during observation, such as Euodia suaveolens var. ridleyi , Citrus lucida (Scheff.) Mabb., Glycosmis pentaphylla (Retz.) DC , Lunasia amara Blanco, Melicope latifolia (DC.) T.G. Hartley, Murraya paniculata (L.) Jack., Triphasia trifolia (Burm.f.) P.Wilson, and Zanthoxylum rhetsa DC.