In Canada, you can only possess up to 30 grams of cannabis. This amount is for dried cannabis only, though — the maximum amount changes depending on the type of cannabis:
Fresh weed: 150 grams
Edible cannabis products: 450 grams
Cannabis concentrates: 7.5 grams
Liquid products: 2,100 grams
Cannabis plant seeds: 30 seeds
Cannabis plants: 4 per residence