Male vs Female Windmill Palms: How to Tell the Difference and How They Reproduce

Introduction

Windmill palms (Trachycarpus fortunei) are one of the most reliable cold-hardy palms for the Pacific Northwest. However, many gardeners are unaware that these palms are dioecious, meaning individual plants are either male or female — not both.

Understanding the difference is critical if you want seed production, self-sown seedlings, or long-term propagation success.

Are Windmill Palms Male or Female?

Windmill palms are dioecious palms, meaning:

• Each palm is either male or female

• A female palm will not produce viable seed unless a male palm is nearby and flowering at the same time

There are no visual differences between male and female palms until they reach flowering maturity, which typically occurs after several years of growth.

How to Identify a Male Windmill Palm

Male palms produce pollen-bearing flower clusters.

Key characteristics:

• Flowers are small and bright yellow

• Flower clusters are dense and powdery

• When disturbed, they release visible pollen

• Male flowers dry up and fall off after pollen release

• Male palms never produce seed

Male palms are often noticed first because their flowers are showy and fragrant when in bloom.

How to Identify a Female Windmill Palm

Female palms produce seed-bearing flower clusters.

Key characteristics:

• Flowers are greenish-yellow, not bright yellow

• Clusters appear less fluffy than male flowers

• After pollination, flowers develop into round green fruit

• Fruit matures to dark blue-black seed

• Seeds hang in large drooping clusters

Only female palms produce seed — but only if pollinated.

How Windmill Palms Are Pollinated

Pollination occurs primarily through:

• Wind

• Insects (secondary role)

For reliable seed production:

• A male palm should be within reasonable proximity (same property or nearby)

• Flowering periods must overlap

In many neighborhoods, even if you only have one palm, pollen from nearby palms may be sufficient.

Bees love the male flowers, in mid bloom you can hear the bees in a palm 30 feet tall. Palms in close proximity seem to pollinate more than palms that are alone or sparsely populated.

Seed Development Timeline

Once pollinated:

1. Flowers develop into green fruit

2. Fruit enlarges over several months

3. Seeds mature by late summer or fall

4. Fully mature seeds turn dark blue to black

Seeds that remain green are not viable.

How Windmill Palms Propagate by Seed

Windmill palms do not produce offshoots. They reproduce only by seed.

Natural propagation:

• Seeds drop near the parent palm

• Germinate in warm, moist soil

• Seedlings often appear the following spring or summer

Intentional propagation:

1. Collect ripe black seeds

2. Remove outer fruit pulp

3. Soak seeds in water for 24–48 hours

4. Plant in well-draining soil

5. Maintain warm temperatures (70–85°F)

6. Germination occurs in 1–3 months, sometimes longer

Seed-grown palms develop stronger root systems than transplanted specimens. It has been our experience that temps don't have to be that high for seeds to start.

Why This Matters for PNW Gardeners

Understanding palm sex helps you:

• Know whether seed production is possible

• Identify volunteer seedlings

• Select palms intentionally for propagation

• Avoid confusion when flowers appear but no seed forms

It also explains why some palms seed heavily while others never do.

Conclusion

Male and female windmill palms are indistinguishable until flowering, but once you know what to look for, identification is straightforward. Seed propagation is the only reproduction method for Trachycarpus fortunei, making mature female palms valuable contributors to cold-hardy palm cultivation in the Pacific Northwest.