How do you get rid of the ants in your greenhouse?

Answers I've found elsewhere:

Eucalyptus oil in the watering can

Clove oil in the watering can

(Tansy companion planting - for next year?)

Talcum powder

Cinnamon powder

Peppermint oil

Diatomaceous Earth (food grade)

"water water and more water they hate being flooded" - also try soaking pots in a tub