The first quarter for the cannabis industry has been a bountiful one, while the stock market is also off to its strongest start to the year since ’91. The broad-based S&P 500 (SPY) tacked on 13% for the first quarter, but the Horizons Marijuana Life Sciences ETF, a basket cannabis stocks, grew 54% in the same period. The North American legal cannabis market generated $12 billion last year, and analysts predict that the market will reach $25.5 billion by 2021, according to a report by Cannabis Business Plan. The growth can be contributed to increased legalization and the increased use of cannabis in medical applications. As the cannabis sector continues to grow, investors continue to place their bets on several cannabis stocks.Top 4 Marijuana Stocks To Watch This Month