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17 September 2014
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how to be a gardener - The complete online guide

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2 - Plant types
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The humble bulb

Now here's a botanical can of worms. At first glance it looks obvious. The term 'bulb' is actually used to describe those little chaps, like daffodils, tulips and bluebells, that pop up in the spring, flower, the leaves hang around for a bit and by summer they've disappeared - until next spring. A true bulb, such as a daffodil is a modified stem.

The mysterious corm

Corms such as crocus, gladiolus and freesia are enlarged stem bases, and each year a new corm grows from a bud on the current year's one.

A tuber

Tubers such as dahlia, cyclamen, and Anenome blanda are stems or roots that have swollen with food stores. A potato is a stem tuber!

A rhizome

Rhizomes such as bearded iris, ornamental ginger and canna lily are modified stems that creep horizontally underground and produce roots.

Oh, and if you're wondering why 'bulbs' go to all this bother, it's a 'survival technique'. Many 'bulbs' live in places where the weather gets extreme. Lots of tulips come from Iran and Iraq where summer temperatures would frazzle them. So, they have developed a lifecycle where they 'do their thing' and get back to safety below ground before the harsh weather sets in.

2. Understand plants

Plant types
 Annuals and biennials
 Perennials and bedding plants
 Woody plants
 Evergreen and deciduous plants
Plant names
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