Agapanthus · Norman, Oklahoma, United States
When to sow agapanthus in Norman
Main outdoor window
1-29 Apr
The window this page is built around.
Timed from last spring frost
25 March
In Norman, on your chosen risk.
Ready to pick
1 Jul - 31 Aug
If you plant at the start of the window.
The average last frost. Half of all years are later than this.
Step by step in Norman
Each window is a range, not a single day. Earlier in the range buys you a longer season; later in it buys you a safer one.
Plant the crowns
1-29 Apr
After the last frost, once the soil has warmed. This crop is never fully dormant, so it cannot be planted bare-root in winter.
In flower
1 Jul - 31 Aug
Agapanthus through the year
Against the frost risk in Norman
Why these dates
Plant in spring once frost has passed, shallowly, with the crown at soil level. Resist repotting: a plant moved into a larger container puts everything into leaf and skips flowering for a season or two. Expect the first real display in year two.
The deciduous types are hardy to about -8C and the evergreen ones several degrees less. Below zone 8 grow it in a pot and move it somewhere cool and frost-free for winter, keeping it nearly dry.
Agapanthus are planted once and then left in place, so there is no sowing offset to resolve. Nor is there a dormant season to plant into: this crop keeps its leaves and keeps growing through the winter, which is exactly why cold damages it. The window on this page therefore waits until the last frost in Norman has passed and the soil has begun to warm, giving the roots the longest possible run before the cold returns.
Hardiness is not the obstacle here. Norman is zone 8a, comfortably inside the range this crop is rated for, so an established plant should come through an average winter without protection.
Do not expect a crop in the first year. A plant set out now should give its first worthwhile pick around year 2, and will then produce every year after that, which is what makes the planting decision worth getting right the first time.
Also in Norman
Other flowers to time
Growing agapanthus in Norman
When should I plant agapanthus in Norman?
Aim for 1-29 Apr in an average year. If you would rather not gamble on the weather, wait until 23 Apr - 21 May - by then frost has finished in nine years out of ten.
When will agapanthus be ready to harvest in Norman?
Expect to start picking around 1 Jul - 31 Aug, based on 150 to 190 days to maturity from the planting date calculated for this location.
How much frost will agapanthus tolerate?
The deciduous types are hardy to about -8C and the evergreen ones several degrees less. Below zone 8 grow it in a pot and move it somewhere cool and frost-free for winter, keeping it nearly dry.