Growing a jacaranda from seed is one of the most rewarding projects a gardener can undertake. There is something deeply satisfying about watching a tiny seed transform into a magnificent tree that will eventually produce its own spectacular purple blooms. While the journey requires patience—seed-grown jacarandas take 7 to 14 years to flower—the process itself is straightforward and achievable for gardeners of all skill levels.
Understanding Jacaranda Seeds
Jacaranda seeds are found inside distinctive flat, round pods that develop after flowering. Each woody pod, approximately 5 to 7 centimetres in diameter, contains numerous papery, winged seeds. Understanding the nature of these seeds helps ensure successful germination.
Seed Viability
Fresh seeds germinate best, with germination rates declining as seeds age. Seeds collected within the current season typically show germination rates of 70 to 90 percent, while older seeds may germinate at significantly lower rates. If purchasing seeds, buy from reputable suppliers who can confirm their freshness.
Seed Variation
It is important to understand that seed-grown trees may differ from their parent in flower colour, intensity, and form. This is because jacarandas are often cross-pollinated, and seeds carry genetic material from two parents. If you want a tree identical to a particular specimen, grafting is the only reliable method.
The rare white jacaranda (Jacaranda mimosifolia 'Alba') can be grown from seed, but offspring may revert to purple or show intermediate colours. For guaranteed white flowers, obtain a grafted specimen.
Collecting Your Own Seeds
If you have access to a mature jacaranda tree, collecting your own seeds is free and ensures freshness.
When to Collect
Seed pods mature in late summer to autumn, several months after flowering ends. Ripe pods are brown, dry, and beginning to split along their edges. Collect pods while they are still on the tree but just beginning to open—pods that have fallen may have already released their seeds.
Extracting Seeds
Allow collected pods to dry fully in a warm, well-ventilated area for a week or two. Once completely dry, the pods will split easily, releasing the papery seeds inside. Shake or gently pull pods apart to extract the seeds. Store seeds in a paper envelope in a cool, dry location until you are ready to plant.
Preparing Seeds for Germination
Jacaranda seeds have a moderate germination rate that can be improved with proper preparation.
Soaking Treatment
Soaking seeds in water before planting softens the seed coat and speeds germination. Place seeds in a container of room-temperature water and soak for 24 hours. Seeds that sink are generally viable; those that float may be less so but can still be planted. Drain and plant immediately after soaking.
Scarification (Optional)
Some gardeners gently scarify the seed coat before soaking to further improve water absorption. Lightly rub the seed between two pieces of fine sandpaper, being careful not to damage the seed interior. This step is optional but may slightly improve germination rates for older seeds.
- Use fresh seeds when possible for best germination
- Soak seeds for 24 hours before planting
- Optional: lightly scarify seed coat before soaking
- Plant immediately after soaking
Step-by-Step Germination
Step 1: Prepare Containers and Medium
Use seed trays, small pots, or recycled containers with drainage holes. Fill with a well-draining seed-raising mix—a combination of peat (or coir), perlite, and sand works well. Avoid using garden soil, which may contain pathogens and drain poorly.
Step 2: Sow the Seeds
Sow seeds about 5 to 10 millimetres deep. Plant several seeds per container, as not all will germinate. Cover lightly with the seed-raising mix and gently firm the surface. Water gently using a fine spray to avoid disturbing the seeds.
Step 3: Create a Humid Environment
Cover containers with clear plastic wrap or a propagation dome to maintain humidity. Place in a warm location with temperatures between 20 and 25°C. Avoid direct sunlight, which can overheat the enclosed environment.
Step 4: Monitor and Wait
Check moisture levels regularly and mist if the medium begins to dry. Remove the cover briefly each day to prevent mould growth. Germination typically occurs within 2 to 3 weeks but can take longer with older seeds or cooler temperatures.
Step 5: Post-Germination Care
Once seeds germinate, remove the plastic cover and move seedlings to a location with bright, indirect light. Keep the soil consistently moist but not waterlogged. When seedlings develop their first set of true leaves (the second pair to emerge), they are ready for transplanting.
Start seeds in early spring for best results. This gives seedlings the entire growing season to develop before their first winter. In tropical and subtropical regions, seeds can be started almost year-round.
Transplanting Seedlings
Handle young jacaranda seedlings carefully, as their roots are delicate and easily damaged.
Potting Up
When seedlings have 2 to 4 true leaves, transplant them into individual pots approximately 10 to 15 centimetres in diameter. Use a quality potting mix with good drainage. Handle seedlings by their leaves, not their stems, which are easily crushed.
Hardening Off
Before planting seedlings outdoors, gradually accustom them to outdoor conditions over 1 to 2 weeks. Start with a few hours of morning sun, gradually increasing exposure and including some afternoon sun. This hardening-off process prevents transplant shock.
Planting Out
Seedlings can be planted in their permanent location once they reach 30 to 50 centimetres in height and have developed a sturdy root system. Choose a sunny location with well-draining soil. Follow proper planting techniques as outlined in our planting guide.
First-Year Seedling Care
The first year is critical for establishing young jacarandas. Provide consistent care to build a strong foundation for future growth.
- Watering: Keep soil consistently moist but never waterlogged. Young seedlings have limited root systems and cannot tolerate drought.
- Fertilising: Apply a diluted liquid fertiliser every 2 to 4 weeks during the growing season. Use a balanced formula at half the recommended strength.
- Protection: Shelter seedlings from extreme heat, strong winds, and frost during their first year. A position with morning sun and afternoon shade is often ideal.
- Pest monitoring: Check regularly for aphids and other pests that target tender new growth.
The Journey Ahead
Growing jacaranda from seed is a long-term commitment, but the rewards are immeasurable. Over the coming years, you will watch your seedling develop from a delicate sprout into a substantial tree. You will learn its individual character and quirks. And eventually, after years of patient nurturing, you will experience the incomparable thrill of seeing your tree burst into its first glorious purple bloom.
For ongoing care of your developing tree, consult our comprehensive care guide and beginner's growing guide.