Bupleurum (Thoroughwax) in Zone 6a & 6b
Bupleurum rotundifolium
When to plant bupleurum (thoroughwax) in zone 6b
Zones 6a and 6b share the same average frost dates in our data, so this page covers both.
Method: Either: Start indoors for an earlier harvest, or direct-sow outside for less fuss. Bupleurum (Thoroughwax) tolerates either.
| Start indoors | Mar 7–Mar 14 |
|---|---|
| Direct sow / transplant outside | Apr 11–Apr 18 |
| Estimated bloom | Jul 10–Jul 17 (~90 days after planting) |
Spacing: 2 per square foot (square-foot-gardening spacing). Mature height: 2-3 ft.
Bupleurum, also called thoroughwax, is a chartreuse-toned filler flower that reads more like foliage than bloom in a bouquet, useful for softening bolder cut flowers without pulling attention away from them.
How bupleurum (thoroughwax) fits zone 6's season
Zone 6b's frost-free window runs about 173 days, from April 25 to October 15. Bupleurum (Thoroughwax) needs about 90 days from sowing to first harvest.
Good companions
No standout companions recorded yet for Bupleurum (Thoroughwax).
Where to buy bupleurum seeds
See why we recommend these suppliers →
As an Amazon Associate we earn from qualifying purchases. Some links on this page also go to other retailers we may earn a commission from as an affiliate, at no extra cost to you. We only recommend products with a genuine consensus of positive, independent reviews. See the sources cited on each item.
See it growing
Search YouTube for "growing bupleurum (thoroughwax)" videos → (a live search, not a hand-picked video; results vary and aren't vetted by us)
← Back to the full zone 6b calendar · Full companion planting guide · Full plant profile · Plan your beds in the Garden Designer →
%20in%20USDA%20zone%206b%3A%20when%20to%20start%20seeds%20indoors%2C%20when%20to%20direct-sow%2C%20and%20when%20to%20expect%20a%20bloom.)
Pin this for later
Growing Bupleurum (Thoroughwax) in USDA zone 6b: when to start seeds indoors, when to direct-sow, and when to expect a bloom.
Save to Pinterest