From Oryx roundabout take the street that goes direction Education city and keep going straight direction Dunkhan. Drive for about 20 min until you reach a croassroad where on the left you see a property sourrounded by walls and the entrance looks like a fort or a castle. The plant shop is on the opposite site of the main street, so from the main street just turn right. There's a huge plant shop there, but you don't even notice it from the street so pay attention to the castle/fort property otherwise you miss it. Prices are much cheaper then shops in Doha.