I grew Gomphrena (globe amaranth) for the first time in 2023 and tested them out both in the landscape (Circle Garden) and in containers. They performed very well, with little pest damage and required little care, although Gomphrena is slow to get going and doesn’t really fill out until mid-summer. The plants in the Circle Garden also flopped over the edges a bit by the end of August.
This is my personal 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 Gomphrena Gnome Mix.
FAVOURITE VARIETIES AND SOURCES
I prefer solid-colour varieties to bi-colour ones.
Stokes Seeds
- Ping Pong Lavender
- Ping Pong Purple
- Gnome Mix – new for 2024
Since Ping Pong was a bit floppy in the border edges of the Circle Garden, I’m going to try Gnome Mix, which is supposed to be about 6 inches / 15 cm high (versus 16-20 inches or 40-50cm for Ping Pong series)
| Hardiness | Annual, not frost-tolerant |
| Exposure | Full sun |
| Deer Resistant | Yes |
| Bloom | Summer to Fall |
| Deadheading | Not really needed |
| Water/soil | Average |
| Width | about 1 foot, get very bushy, well branching |
| Height | Most reach 18 to 24 inches high |
Notes:
Gomphrena is slow to get going, both as seedlings and after I transplanted into the garden. They did not really begin to fill in until July, when I gave them a boost of water-soluble fertilizer even in the garden beds. After that, they got quite bushy. That makes spacing a challenge if mass planted, as the garden bed looks sparse for 6 to 8 weeks. I hope switching to a low grower yet still spacing the plants close together in the border edges will solve this.
Plants in containers did better, likely because of the slow-release fertilizer.
Also, I recently read that the leaves can be made into a tea – I might try that next year (along with my camomile).
SEED STARTING
- 8 weeks before frost is March 25
- needs darkness to germinate, so cover 1/8 to 1/4 inch with soil (I did not cover more than that, and they germinated very easily)
- sow about 6 seeds per inch, then prick out and transplant
- seeds prefer warmth to germinate at 80°F (27°F) – use a heat mat
- germinates in 7 to 14 days
GROWING CONDITIONS
- Gomphrena seedlings are very slow growers, have patience
- No need to pinch; it will branch naturally
- Consider using grow lights until they have two sets of true leaves
TRANSPLANTING TO GARDEN
- Plant out at the end of May, after the risk of frost is past
- Full maturity in the garden is long – 85 to 100 days
- Lightly fertilize when the first flowers appear
- Needs good drainage, or the bottom stems will rot and break