Zone: n/a
Soil: Sand to clay
Light: Full to part sun
Bloom colour: Red to yellow to pink
Bloom period: Early summer onwards
Height: 12 to 36 inches
Moisture: Dry to medium
Attracts: A variety of bees, butterflies, other insects, birds and sometimes hummingbirds.
Notes: Zinnias are elegant annual flowers from Mexico that have deservedly become quite popular. They attract a large range of animals and are probably the best annual to plant in a wildlife garden. Tney are especially good for butterflies because the large flowerheads provide a flat landing platform. On California giants, there are somewhere between 10 and 30 disc florets on one flowerhead and each floret is a small flower from which butterflies can extract nectar. Offering so many nectar rich flowers in one place reduces the flying time of butterflies and makes for efficient foraging. They start to bloom in July and then the flowers just keep coming. As the season progresses, the flowers become more profuse. Zinnias are planted in ornamental and managed wildlife gardens where they contribute a long season of bright colour.
There are many varieties of Zinnia and they are not all the same in their ability to attract pollinators. I use California Giants, which is an heirloom variety developed in the 1920s. If you want to attract pollinators, avoid any hybrids because they may not produce much nectar and avoid any cultivars that produce double flowers because the disc florets in the centre will be inaccessible. California giants are a selection from one species, Zinnia elegans. Their disc florets are visible and accessible for open pollination. In addition to being more prominent in the landscape, flowers that grow well are likely to be healthier and therefore richer in nectar. Taller flowers are therefore preferred by pollinators.
To get the best out of these flowers, plant them en masse. They are easy to grow and tolerate some dryness once they are established. They do well in sandy soil. However, if you are growing them in containers where they get planted close together, then make sure that they get plenty of water. California giants, in particular, will need more water due to their size.
Leave a good proportion of flowerheads on the plant at the end of the season. The flowers will self-sow and you will enjoy watching the goldfinches eating the seeds. If you have ornamental island gardens, then low zinnias make a great edge plant. Again, look for open pollinated selections of Zinnia elegans.
The best way to get these plants is to buy seed. They are easy to germinate under a light and seem fairly resistant to damp off. The small amount of extra effort required to raise Zinnia from seed more than pays off with extended period of fantastic colour and pollinator activity. |
