Discover how to grow phlox from seed with our step-by-step guide, featuring tips and tricks for creating a beautifully scented garden.
The sweet scent and delicate petals of phlox makes it an irresistible addition to any garden. Annual phlox, also known as Phlox drummondii, features star-shaped flowers in dense clusters, creating a stunning display of color.
Phlox flowers also attract pollinators like bees and butterflies, which contribute to a healthy and thriving ecosystem. These versatile plants can be grown in garden beds, borders, containers, or even hanging baskets, making them an excellent choice for gardeners of all experience levels.
Luckily, it’s easy to grow phlox from seed, so you can plant large drifts of color and fragrance without breaking the bank! In this article, Ill share my tips and tricks for growing phlox from seed so you can include this low-maintenance plant in your garden plans this year!
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Phlox is a low-maintenance plant with many US native species. You’ll often find it growing wild in partly shaded woodlands, meadows, and along streams. Some varieties are perennial, forming low mounds that grow back from the roots each year. Other cultivars are annuals, which is what Ill be focusing on in this article.
There are at least 60 species of phlox that come in a wide array of flower colors such as red, pink, bi-colored, blue, white, and lavender. This year, Im growing Cherry Caramel Phlox, which are the pale yellow flowers with a pink eye in the photo below, and Sugar Stars Phlox, which youll see later on.
Hey there fellow gardeners! I’ve been growing phlox for years and one question I get asked a lot is about identifying phlox seeds. Let me share everything I know about these tiny treasures that create such beautiful blooms in our gardens.
Quick Answer
Phlox seeds are small (1-2mm), oval to teardrop-shaped seeds that start pale green and mature to dark brown. They’re housed in buff-colored roundish capsules that crack open when ready for harvest.
Physical Characteristics of Phlox Seeds
Let me break down exactly what you’re looking for
- Size: Tiny! About 1-2 millimeters long
- Shape: Oval to teardrop-like, slightly flattened
- Color: Initially pale green, turning dark brown when mature
- Texture: Rough and pitted surface
- Special Feature: Tiny cream-colored attachment point on one end
The Seed Pod Structure
The seeds don’t come alone – they’re packaged in nature’s little container:
- Round, buff-colored capsule
- Becomes dry and brittle when mature
- Each flower produces one seed pod
- Pod splits naturally when seeds are ready
- Contains single black oblong seed inside
How to Harvest Phlox Seeds
Here’s my tried-and-true method for collecting phlox seeds:
- Timing: Wait until late summer/early fall
- Selection: Choose healthy blooms that have finished flowering
- Signs of Readiness:
- Flowers completely faded
- Seed pods turned yellowish-brown
- Pods feel dry and brittle
Step-by-Step Harvesting Guide
- Stop deadheading flowers you want to collect seeds from
- Wait for pods to turn brown (but don’t wait too long!)
- Snip pods with scissors or pruners
- Place in paper bag or envelope
- Let pods dry for 1-2 weeks
- Gently crack pods to release seeds
- Store cleaned seeds in paper envelope (not plastic!)
Storage Tips
I’ve learned these storage tricks the hard way
- Keep seeds in paper envelopes (never plastic – trust me on this!)
- Label with:
- Plant name
- Color
- Date collected
- Store in cool, dark, well-ventilated spot
- Add rice grains to absorb excess moisture
- Seeds stay viable for 2-3 years when stored properly
Planting Your Phlox Seeds
Ready to plant? Here’s what works best:
Direct Sowing
- Plant in spring after frost danger passes
- Cover lightly with 1/8 inch soil
- Space seeds 1 inch apart
- Keep soil consistently moist
- Germination takes 5-10 days
Container Planting
- Use 2-4 seeds per pot
- Ensure pot has drainage holes
- Space plants 6 inches apart
- Use well-draining potting mix
- Place in full sun to partial shade
Pro Tips from My Garden
Over the years, I’ve discovered these helpful tricks:
- Dark germination is crucial – phlox seeds need complete darkness to sprout
- Don’t fuss about soil quality – they’re pretty adaptable
- pH preference: slightly acidic (6.0-8.0)
- Add aged compost for better drainage
- Consider afternoon shade in hot climates
Common Mistakes to Avoid
We all make mistakes! Here are some I’ve made so you don’t have to:
- Waiting too long to harvest (seeds will scatter!)
- Using plastic bags for storage (hello, mildew!)
- Exposing seeds to light during germination
- Overcrowding plants
- Overwatering established plants
Final Thoughts
Identifying and collecting phlox seeds might seem tricky at first, but once you know what to look for, it’s pretty straightforward. Remember, those tiny brown seeds in their buff capsules are your ticket to a gorgeous garden next season!
Happy gardening, everyone!
How to Plant Phlox Seeds
While phlox prefers to be direct sown into the soil where you want them to grow, you can also grow phlox from seed indoors with a little extra care. Heres how!
When to plant phlox seeds
Plant phlox seeds indoors 4 to 6 weeks before the last frost date for your area. Sow the seeds outdoors when the soil becomes workable in spring, up to two weeks before the last frost.
What Do Phlox Seeds Look Like – A General View
FAQ
Can you grow phlox from seeds?
Plant Phlox seeds in a potting soil and space them 1 inch apart and 1/8 inch deep. Mist the top of the soil with a spray bottle. To help retain moisture, cover the container with a plastic bag and keep the seeds in a warm, dark area indoors. Phlox seeds should germinate in 10 days.
Will phlox reseed itself?
Phlox will reseed itself so there need never be a year without these lovely flowers. Deadheading phlox blooms will prevent much of that reseeding. Removing phlox flowers that are spent has this benefit and a few others as well. Some gardeners deadhead phlox flowers to confine the spread of the plant.
How long does it take for phlox seeds to sprout?
At around 70 F, phlox will germinate in a week or two – just keep peeking under the lid to see if they’ve started germinating or not. Once the seeds have started germinating, you’ll want to get the burgeoning young seedlings under light.