Here's a card I made for a former colleague, a Biology teacher whose classroom was always full of plants! It's a quick and easy design, and cacti are a really popular motif at the moment (I think I was partly inspired be the lovely plant pins I got recently!).
To make the card, all I did was to cut out a pot from stripy paper, cut out the cactus shapes from green patterned paper using pinking shears, and add some punched flowers. I added some ink round the edges for definition using a stamp pad.