I’m always looking for new annuals to use in pots and containers that are deer-tolerant. I decided to try Alternanthera and what a beautiful foliage plant. Alternanthera grows quite large although you could clip it as it branches easily. The foliage of Purple Prince is brown-red and best of all showed no signs of pest damage all season. I had some planted in full sun, some in morning sun and afternoon shade and both areas did equally well.
Alternanthera Purple Prince starts from cuttings, roughly 8 weeks
I grew mine from seed the first year. Germination was about 50% but that could have been me as I tend to overwater starts and these have to be surface sowed. They were also slow to get growing. I have lots to learn about that!
In the fall I took a few clippings and put them in water. They rooted easily, grew very fast and I now have two mother plants in the greenhouse to create more plants for the spring so growing Alternanthera from cuttings may be the better way to go.
This is my personal garden growing guide. I use it to track seed sources, when to start seeds and if I should adjust growing conditions in my own greenhouse and garden. Please don’t consider this professional grower’s advice. I like the plant information cards from Ball Seed. Here is Purple Prince Alternanthera.
| Hardiness | Annual |
| Exposure | Sun to part shade, colour better in full sun |
| Deer Resistant? | Yes |
| Bloom | Small white blooms in summer, although I did not see any |
| Habit | Spreading, well-branched, spiller |
| Deadheading | None. Clip back for size if needed |
| Height | 10-16 inches |
| Width | 18-20 inches |
SEED STARTING
- 10-12 weeks before frost (mine grew slow, so I’d sow earlier if you want a 3-inch pot size by transplant time)
- Seedlings grow slowly, taking 4-5 weeks before transplant, so use small pots to start, aka 6-cell pack
- Surface sow, press lightly – do not cover. Seeds need light to germinate.
- Germination is best at 80°F (26°C), so use heat mats. Germinates in 7 to 10 days.
- Use bottom heat and water with warm water.
GROWING CONDITIONS
- Transplant into 4 inch pots in 7 to 8 weeks
- Plant starts to take a while to get to transplant plug size – hence try from cuttings instead
- Apparently, lots of light prevents flowering.
- Watch for aphids although I have not had a problem (they are all over my over-wintered dipladenias though)
I did not use a lot of extra fertilizer in the containers over the season. I put in slow-release pellets and then fertilize with a water-soluble fertilizer once a month and mine grew very large by fall.