Representing eternal life in Hindu mythology, banyan trees (Ficus benghalensis) are known as the "wish-fulfilling tree." As a tropical tree growing up to 200 metres (656 feet) wide and 30 metres (99 feet) wide in its native India and Pakistan, growing it to maturity in the UK would indeed be wish fulfillment, but gardeners can still enjoy banyans for several years as large houseplants or conservatory specimens. Banyan seeds normally pass through a bird's digestive system before germinating in the wild, so gardeners must overcome the seeds' protective properties to increase their chances of success.
Fill a plastic with water heated to about 45 degrees Celsius (113 Fahrenheit). The water should feel hot but not scalding. Drop banyan seeds the water and seal the container with its lid. Leave for 12 hours. This helps dissolve the chemicals in the seed coating inhibiting germination, and also softens the hard shell.
Drain container of water, retaining seeds. Fill plastic pots with potting compost. Push two seeds, spaced apart, into each pot. Germination rates are likely to be low, so sowing two seeds per pot helps economise on pots and compost. Stand pots in 1 cm (1/2 inch) water until compost is damp on the surface. Remove pots from water and leave to drain.
Place pots with banyan seeds in a heated, unused area of the house, frost-free greenhouse or conservatory. Alternatively, put them in a plant propagator set to about 20 degrees Celsius (68 degrees Fahrenheit). At this stage the seeds don't require light, so keeping them in an airing cupboard would also be suitable. Avoid exposing the pots to temperature fluctuations. Water as needed to prevent compost drying out. Banyan tree seeds may take several months to germinate.
Check pots every three or four days. At the first sign of sprouting, move seedlings into a bright, warm area such as a heated greenhouse or conservatory and continue to water as needed. Banyan seedlings can't tolerate direct sunlight.
Grow seedlings on, moving into slightly larger plant pots when their roots fill their pots. Mist with a fine spray of rainwater every day to help recreate the plants' preferred humid growing conditions.
Wipe dusty leaves with a soft, dampened cloth to allow more light to penetrate.
Exposing pots to freezing temperatures and dry or saturated compost kills germinating seeds. Spraying banyan leaves with leaf shine products clogs up leaf pores and is harmful to plants.