 Public name
Indonesia : Kembang Kertas, Kembang ratna
England : Zinnia
China : Bai fi ju



Classification
Kingdom : Plantae
Super Division : Spermatophyta
Division : Magnoliophyta
Class : Magnoliopsida
Sub Class : Asteridae
Order : Asterales
Family : Asteraceae
Genus : Zinnia
Spesies : Zinnia elegans Jacq.

Description:
Zinnia elegans standing grow, tall 30-75 cm. Flower is simple, calyx have color full. Stem rough haired. Leaf: green, position of leaf is face to face; shape of leaf is elongate; top of leaf is pointed; embrace to stem; margin of leaf is integer; venation (sceleton) is palminervis.

Usage:
Zinnias are traditional in annual flower beds and borders. Use the dwarf varieties in containers and window planters. Grow the taller varieties in borders and beds and for cut flowers. Pinch young stems back to encourage branching unless growing for long-stemmed cut flowers. Deadhead spent flowers frequently to prolong flowering. Zinnias will produce larger (but fewer) flowers if you remove side shoots.

Blooming:
In the greenhouse, the plants will bloom all year long. Flowers come in single and double forms and sizes. Flowers range from 2 inches (5 cm) to 5 inches (13 cm) across.

Culture:
Zinnia elegans hybrids need full sun to light shade with a rich well drained soil mix. In the greenhouse, we use a soil mix consisting of 2 parts peat moss to 1 part loam to 1 part sand or perlite. For each 0.01 cu. yards of soil mix, we add 1 cup of 14-14-14 osmocote slow release fertilizer, 1 cup hydrated lime to adjust pH and 1 teaspoon of micromax micronutrients. This gives the soil mix a pH of 6.5 and enough nutrients to grow and flower quickly. The plants are well watered and allowed to dry slightly before watering again. In the landscape, zinnias are fairly drought tolerant, but less so in containers. The only problem with growing them in the greenhouse is that aphids can become a problem, which is why we grow them for IPM experiments. If plants are kept deadheaded, the flowering period is extended. At the end of classes, we collect the seed for the next set of classes, and the plants are allowed to die off. When growing in the winter months, supplemental lighting is needed.
Propagation:
Zinnia elegans hybrids are best propagated from seed. Seed germinates in 7-14 days from sowing.




Reference
Tjitrosoepomo, Gembong. 2005. Morfologi Tumbuhan. Yogyakarta: Gadjah Mada University Press.
http://www.plantoftheweek.org/week433.shtml.