Aphria (NASDAQ:APHA) ranks as one of the hottest pot stocks on the market so far this year. Shares of the Canadian cannabis producer have more than doubled in 2021.

Meanwhile, Curaleaf Holdings (OTC:CURLF) has delivered a nearly disappointing performance compared to last year. Curaleaf stock is up 16% year to date versus a 90% gain in 2020.

Investors are more focused on the future than the past, though. Which of these cannabis stocks is the better pick going forward? Here's how Aphria and Curaleaf stack up against each other.

Giant cannabis leaf in a shopping cart

Image source: Getty Images.

Aphria: A soon-to-be 800-pound gorilla 

Probably the best reason to consider buying shares of Aphria is that the company will soon become an 800-pound gorilla in the cannabis world. Aphria's pending merger with Tilray (NASDAQ:TLRY) will result in the creation of the biggest global cannabis company based on pro forma revenue. 

Although the combined entity will be named Tilray, Aphria will be firmly in the driver's seat. Aphria shareholders will own 62% of the post-merger company. Current Aphria chairman and CEO Irwin Simon will hold the same positions in the "new" Tilray.

The combined company will claim the largest market share in the Canadian adult-use cannabis market. It will be a major player in European medical cannabis markets with Aphria's CC Pharma distribution business paired with Tilray's big cannabis production facility in Portugal.

There's a huge market, though, that Aphria in its current or future forms can't compete in yet: the U.S. cannabis market. However, that just might change in the not-too-distant future. If it does, Aphria's Sweetwater craft beer business (which focuses on what it calls "cannabis lifestyle" craft beer brands) and Tilray's Manitoba Harvest hemp foods unit could give the combined entity a solid launch pad to enter the U.S. pot market.

Curaleaf: The biggest U.S. player that's getting even bigger

Curaleaf already ranks as the biggest U.S. cannabis retailer with more than 100 dispensaries in operation. It's also the largest U.S. cannabis company based on sales. And Curaleaf is about to grow even bigger. 

The company currently has a presence in 23 states. Curaleaf claims the No. 1 market share in Connecticut, Maryland, Massachusetts, New Jersey, New York, North Dakota, Pennsylvania, and Vermont. Its retail market share is also in the top three in Arizona, Florida, Illinois, and Maine. 

Curaleaf has a massive opportunity ahead of it in one of the states where it's already the top player. New York recently legalized recreational marijuana. Look for Curaleaf to leverage its 25%-plus market share in the state's medical cannabis market to establish a leadership position in the recreational pot market as well.

New York isn't Curaleaf's only major growth market, though. The company has opened new retail locations in several states over the last few months, including Florida, Illinois, and Pennsylvania.

Curaleaf's radar isn't limited only to the U.S. Earlier this month, the cannabis operator completed its acquisition of EMMAC, Europe's largest vertically integrated independent cannabis company. This deal gives Curaleaf a strong position in key medical cannabis markets in Germany, Italy, Portugal, Spain, and the United Kingdom. 

Better cannabis stock?

In my view, it's an easy choice between these two cannabis stocks. I like Curaleaf over Aphria.

Aphria's challenges are evidenced by its disappointing Q3 results. The company's distribution revenue and net cannabis revenue fell quarter over quarter. Aphria posted a big net loss. Combining with Tilray won't make those problems go away.

Curaleaf, on the other hand, yet again reported strong revenue growth in its latest quarter, both on a year-over-year and quarter-over-quarter basis. The company's acquisitions and expansion opportunities should enable it to keep that momentum going.  

This article represents the opinion of the writer, who may disagree with the “official” recommendation position of a Motley Fool premium advisory service. We’re motley! Questioning an investing thesis -- even one of our own -- helps us all think critically about investing and make decisions that help us become smarter, happier, and richer.