Canna
Canna are a common plant in the tropics, but are usually tall hardy varieties that flower infrequently. However, you can buy seeds of varieties that are less hardy (need to be kept in the shade during the hot season and put out in the sun in the cool season). These varieties flower almost continuously and are much smaller.
The seeds need to be soaked overnight before planting and even then may take several months to germinate. The plants need a great amount of water (in the wild, they are semi-aquatic). After a particular stem has finished flowering, it should be cut down to ground level, to encourage more flowering shoots to appear. The plants produce fleshy tubers, so when they get too crowded for your pot, you can divide up the tubers.
The large flowers are usually red/ orange (as above)/ yellow/ pink or white. In my experience, pink although a beautiful colour is not very strong and likely to die on you.
The seeds need to be soaked overnight before planting and even then may take several months to germinate. The plants need a great amount of water (in the wild, they are semi-aquatic). After a particular stem has finished flowering, it should be cut down to ground level, to encourage more flowering shoots to appear. The plants produce fleshy tubers, so when they get too crowded for your pot, you can divide up the tubers.
The large flowers are usually red/ orange (as above)/ yellow/ pink or white. In my experience, pink although a beautiful colour is not very strong and likely to die on you.