House of Terpenes named this drink "Limonene" which is a naturally occurring terpene from the cannabis plant. Terpenes give each cultivar their unique smell and taste, terpenes also have added health benefits. Limonene is a terpene that's also found in lemon rind. However this drink doesn't list terpene extract in the ingredients, so I'll assume it's meant to simply mimic the taste.

Here's the description from the BC Cannabis store online- Limonene Sparkling Tonic is bright and citrusy with notes of lemon, tangerine & thyme.  Dry West Coast hops help to elevate the citrus flavour and add a complex botanical finish that's not overly sweet...best served chilled.

I'd say it tastes earthy with a hint of lemon and tonic water taste. It's not bad, it's different and if you're interesting in trying something unusual, this might be the drink for you.