I would like to send a large bouquet of flowers to my school teacher for her anniversary. Which delivery service in Riga should I use? Where do you usually go?

What type of bouquet do you need? My wife's sister in Latvia makes bouquets to order, but she has only recently started in this business, so the choice of flowers is not yet great. I can give you her Facebook.
If we are talking about large flower delivery, you can turn to this service https://www.krokus.lv/en/. It is very famous and popular in the city.