5 bulbs that become weeds

Watsonia

These do particularly well in sandy soil and in drier climates, and can become great invaders.

Tritonia (Montbretia)

This indestructible plant is also known as Crocosmia, but, whatever it's called, it can be bad news in bushland.

Freesia

The dainty Freesia refracta “Alba” is often seen growing wild on roadsides.

Lilium Formosanum

Who would think that any of the stately liliums could become pests?  Unfortunately, this variety is such a survivor that, under the right conditions, it can take on weedy proportions.

Arum

Because they have a rhizomatous rather than a bulbous rootstock, arum lilies are not always classed as bulbs, but there's no doubt that they can become weeds, especially in damp spots.

This information is from the Yates Garden Guide: fully revised & updated 44th edition, HarperCollins, $39.99. You can have this information and so much more at your fingertips by purchasing the Yates Garden Guide, available at all leading bookstores and Bunnings stores.