Casuarina equisetifolia, Australian Pine, Casuarina equisetifolia.
Description: An evergreen tree up to 35 m tall, with soft, needle-like leaves. The bark is light brown. The graceful, bright green branches are covered with scales—reduced leaves.
In the fall, rather inconspicuous small, perianth-less, unisexual flowers bloom. The male flowers are in thin terminal racemes, while the female flowers are several in spherical, woody inflorescences. In the spring, the winged nut-shaped fruits ripen.
Use: In Russia, it is grown primarily as an indoor ornamental plant and rarely grows more than 2 m. It is suitable for bonsai cultivation.
Growing conditions: Casuarinas should be planted in a sunny location in fertile, moist, well-drained soil. The trees themselves are graceful, fast-growing, resistant to strong winds, and tolerate very dry conditions. They can withstand short-term frosts down to -7°C (16°F).
USDA Hardiness Zone: 9 (-7°C to -1°C (23°F to 32°F)).
Growing from seeds: Method 1. Scarification (not always necessary): soak the seeds in hot water (about 60-70°C (140-158°F)) for 5-10 seconds, then quickly cool them in cool water. Soak the seeds in warm water or a weak solution of a stimulant (Epin, Zircon) for 12-24 hours. Sowing: Spread the seeds on the surface of a moistened substrate: a mixture of peat and perlite (vermiculite) or fine sand (1:1), press lightly, and moisten. Germination Conditions: Temperature: Optimally +22-+26C. Humidity: Cover the container with a transparent lid, glass, or film to create a greenhouse effect. Ventilate daily. Lighting: Bright, diffused light. Watering: Only through the tray or with a spray bottle, so as not to disturb the seeds. Sprouting: Seeds can take 1-2 weeks to 1-2 months to germinate. Be patient. The seedlings are very delicate. When the first true leaves (needles) appear, gradually remove the covering.
Method 2: To increase germination Cold stratification: Mix the seeds with slightly damp, sterilized sand or vermiculite. Place the mixture in a sealed zip-lock bag and store in the refrigerator's vegetable drawer (temperature +2-5°C) for 4-6 weeks. Check periodically to ensure the mixture doesn't dry out or become moldy.
After stratification, sow the seeds superficially as described in Method 1.