How to grow Perennial Phlox

Phlox paniculata

Full Sun
OR
Partial Sun
Medium

Phlox starts into growth in early spring and can be divided at this time. Keep the soil evenly moist to help prevent mildew. Some stems can be cut back to prolong the flowering season.
Cut back spent flower heads to encourage further buds and unwanted seedlings
Clumps can be divided in the autumn after flowering.
Dividing herbaceous perennials rejuvenates the plant, discard old woody matter from the centre of the clump

Growing Perennial phlox from seed

Direct sow outdoors in fall, or under a coldframe or unheated greenhouse in the winter. Requires a period of cold before germination
This can also be achieved by planting the seeds in a pot and after two to four weeks at 18 to 22C transfer to 4C for four to six weeks before returning warmer conditions but no more than 18C. If needed this cold cycle can be repeated if the seeds are still dormant
Much easier by dividing establishes clumps in the early spring or autumn.
Root cuttings will prevent the transmission of eelworm infestations found in the aerial parts of herbaceous phlox

Soil temperature should be kept higher than 15°C / 59°F to ensure good germination.

By our calculations*, you should look at sowing Perennial phlox about 14 days before your last frost date .

Transplanting Perennial phlox

Traditional cottage garden plant, great for borders place in the middle or towards the back.
Requires evenly moist soil in full sun.
Regular lifting and division of established clumps rejuvenates the plant, this can be done in spring or early autumn

Ensure that temperatures are mild and all chance of frost has passed before planting out, as Perennial phlox is a very hardy plant.

Harvesting Perennial phlox

Cut flowers for indoor display whenever you like. Use pruning shears or scissors for clean cut.

Seed Saving Perennial phlox

Phlox do not always come true from seed, phlox is more reliably propagated from root cuttings

How long does Perennial phlox take to grow?

These estimates for how long Perennial phlox takes to sprout, grow and harvest are from real observations from real gardeners, right around the world.

Days to Germination How long does it take Perennial phlox to germinate?: 12 days
Average 12 days | Min 6 days | Max 139 days (4)
Days to Transplant How long until I can plant out Perennial phlox?: + 26 days
Average 26 days | Min 26 days | Max 26 days (1)
Days to Maturity How long until Perennial phlox is ready for harvest / bloom?: + 196 days
Average 196 days | Min 60 days | Max 1930 days (20)
Total Growing Days How long does it take to grow Perennial phlox?: = 234 days

When should I plant Perennial phlox?

Our when to plant Perennial phlox estimates are relative to your last frost date.

When to sow The number of days to sow Perennial phlox before or after your last frost date.: 14 days before Last Frost Date

Perennial phlox Folklore & Trivia

Several old fashioned forms of Phlox paniculata are still available to grow today, Lilac Time from the 1940’s and 50’s is widely sold among the more modern cultivars

Other names for Perennial phlox

Garden Phlox, Phlox, Dwarf phlox, Border phlox

Phlox paniculata L.

Footnotes

¹ “Phlox paniculata” :http://www.daytonnursery.com/Encyclopedia/Perennials/Phlox%20paniculata.htm