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The Garden
February 2005

Fast and flamboyant

Architectural plants need not be expensive, imported, aged specimens. Phil Clayton salutes the versatile annuals, biennials and perennials that can be easily grown from seed for similarly bold effects

Images: Tim Sandall

Growing from seed

Plants with fine seed such as Verbascum should be sown on to the surface of seed compost (1). Larger seeds such as those of Leonotis (2) can be pushed lightly into the compost. These may then be covered with a layer of vermiculite (3) which keeps seed moist but allows the passage of air and light. Both these genera germinate at a temperature of 13-18°C (55-64°F). Prick out seedlings and move them on into single pots when large enough.

Ricinus communis is easy; simply press the pea-sized seeds into the compost (4), keep at 20°C (68°F) and pot on seedlings once large enough to handle.

Seed dormancy

Cleome hassleriana and some other plants germinate best after a period of chilling, which helps them overcome dormancy. Place seeds into an airtight plastic bag (5) with a handful of moist compost and a label, and seal the bag. Place into a fridge (6) for two weeks, then remove and sow in a seed tray at 15°C (59°F). Germination may be erratic.

The seed of Ensete ventricosum is large and can be ‘chipped’ (a small section of the seed coat carefully removed) before sowing in single pots in seed compost (7) at 18-21°C (64-70°F).

Phil Clayton is the Garden Writers’ Guild Horticultural Journalist of the Year

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