Sundial Growers (NASDAQ:SNDL) ranks as the most popular cannabis stock on Robinhood. It's even the third most widely held stock overall among investors using the trading platform. 

Seven other pot stocks are also included in the list of the top 100 most popular stocks on Robinhood. Several of them are arguably better positioned for long-term success than Sundial is. But Robinhood doesn't support trading in many of the best stocks in the cannabis industry because they're only available over the counter. Here are three marijuana stocks better than Sundial Growers that Robinhood investors can't buy.

A cannabis plant with an overlaid image of a white line with an arrow trending up and a $1 bill

Image source: Getty Images.

1. Ayr Wellness

Ayr Wellness' (OTC:AYRW.F) market cap of around $1.1 billion is well below Sundial's $1.7 billion market cap. However, the U.S. multistate operator (MSO) generated over four times more revenue in its fourth quarter than Sundial did.

More importantly, Ayr continues to deliver strong growth. Its Q4 revenue soared 48% year over year while Sundial's revenue declined year over year. Ayr also posted positive adjusted earnings before interest, taxes, depreciation, and amortization (EBITDA) of $19.4 million in Q4. Sundial reported an adjusted EBITDA loss.

Ayr shouldn't have any problems keeping its momentum going. The company's recent acquisition of Liberty Health Sciences gives it a solid position in the fast-growing Florida medical cannabis market. Ayr also completed acquisitions in Arizona and Ohio in March and has a pending deal that will give it a foothold in New Jersey. 

The company projects full-year 2022 revenue of $725 million and adjusted EBITDA of $325 million. That goal seems attainable with Ayr's string of deals. Sundial hopes to make some investments of its own, but Ayr is clearly in a stronger position.

2. Cresco Labs

Cresco Labs (OTC:CRLBF) also offers a much more attractive valuation than Sundial Growers does. Its forward price-to-sales (P/S) ratio is a little over one-tenth the size of Sundial's forward P/S multiple. 

Like Ayr Wellness, Cresco blows Sundial out of the water when it comes to delivering growth. Cresco's revenue nearly tripled year over year in the fourth quarter of 2020 to $162.3 million. The multistate operator generated adjusted EBITDA of $50 million.

Cresco's growth advantage over Sundial is likely to persist. The company expanded its presence in Ohio with its acquisitions of four medical cannabis dispensaries in February. Cresco will soon enter Florida's medical cannabis market with its acquisition of Bluma Wellness

Probably the biggest opportunity for Cresco, though, is in New York. The Empire State recently legalized recreational marijuana. Cresco stands as one of only 10 cannabis operators licensed for vertical operations in New York state. 

3. Curaleaf Holdings

Curaleaf Holdings (OTC:CURLF) is the biggest U.S. multistate cannabis operator and claims a market cap of around $10 billion. Even though it's a lot larger than Sundial Growers, Curaleaf is still a better bargain with a forward P/S ratio 73% lower than its Canadian counterpart.

In the fourth quarter, Curaleaf's total revenue more than tripled year over year to $230.3 million. Its adjusted EBITDA soared 289% to $53.8 million. 

As is the case with Ayr Wellness and Cresco Labs, acquisitions have played a significant role in Curaleaf's phenomenal growth. In particular, the company's July 2020 purchase of Grassroots boosted sales tremendously. Prior to its acquisition by Curaleaf, Grassroots was the largest private vertically integrated MSO in the U.S. 

While the future growth prospects for Sundial are somewhat murky, Curaleaf should have a clear runway for future growth. It already claims the No. 1 market share in New York's medical cannabis market. The company will almost certainly be a leader in the state's recreational marijuana market as well. Curaleaf also recently acquired EMMAC Life Sciences in a deal that will enable the company to expand into European medical cannabis markets.

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.