I fully realize that cannabis stocks right now are about as popular with investors as a New York Yankees jersey is at a Boston Red Sox game. But despite the dismal performance for most cannabis stocks this year, there are some great opportunities for long-term investors.

My attention is primarily focused on the U.S. market, which continues to expand significantly. Three stocks that I think look like great picks to buy in October are Charlotte's Web Holdings (OTC:CWBHF), Innovative Industrial Properties (NYSE:IIPR), and Trulieve Cannabis (OTC:TCNNF). Here's why.

A miniature shopping cart with a marijuana leaf in it, on top of a pile of cash.

Image source: Getty Images.

1. Charlotte's Web

If you think that CBD products will continue to gain traction in the U.S. and elsewhere, you'll probably like Charlotte's Web. The company pioneered hemp CBD and reigns as the No. 1 brand in the total hemp-derived CBD market.

Charlotte's Web reported year-over-year revenue growth of 45% in the second quarter. I expect sales will pick up even more momentum with increasingly more retailers stocking the company's CBD products. Charlotte's Web has more than doubled the number of retail locations carrying its products so far this year. Just a few days ago, it announced that 738 Vitamin Shoppe stores in 45 states had started selling its CBD gummies.

My take is that Charlotte's Web is positioned better than any other hemp CBD company to transition successfully to a major player in the global consumer packaged goods (CPG) industry. It definitely enjoys better brand recognition and a broader retail distribution network. I think that the company also has a stronger management team, with CEO Deanie Elsner and several key executives claiming extensive experience in the CPG industry.

One wild card for Charlotte's Web is what actions the U.S. Food and Drug Administration (FDA) might take with establishing regulations for CBD products. Delays or very tight restrictions on CBD products would hurt the company. However, the cat is out of the bag with CBD -- and the FDA knows it. Over the long run, reasonable regulations for the CBD industry should pave the way for sustained growth for Charlotte's Web.

2. Innovative Industrial Properties

Innovative Industrial Properties, also known as IIP, is more than 30% off its all-time high from just three months ago. I think the pullback presents a great buying opportunity.

It's important to first understand why IIP's shares have retreated. The company announced in July that it was selling 1.3 million shares to raise cash. This caused dilution in the value of existing shares and was reflected in IIP's lower offering price for the stock offering. In addition, overall weakness among cannabis stocks weighed on IIP.

But what's even more important is that IIP's business prospects haven't weakened one bit. In my view, those prospects are even stronger now that the cannabis-focused real estate investment trust (REIT) has nearly $164 million in additional cash to invest in new properties thanks to its stock offering.

I really like IIP's "rinse-and-repeat" business model of investing in cannabis properties, leasing them out to achieve attractive long-term returns, and then reinvesting its cash into expanding even more. With several state medical cannabis markets still in their early stages, IIP should have plenty of opportunities to rinse and repeat in the future.

3. Trulieve Cannabis

One of IIP's tenants is another of my favorite cannabis stocks to buy in October: Trulieve Cannabis. But while Trulieve leases a property in Massachusetts from IIP, it's the company's Florida opportunity that's really intriguing.

Trulieve currently operates 33 medical cannabis dispensaries in Florida. It expects to bump up that total to 44 stores by the end of 2019. And Trulieve absolutely dominates in the state's medical cannabis market with a market share of nearly 50%. The No. 2 company in Florida claims a market share of less than 14%.

The medical cannabis market in Florida could soar to more than $1.7 billion by 2022. If Trulieve can maintain its current market share, the company could be on track for annual sales of close to $800 million in the not-too-distant future. That's exciting for a stock with a current market cap of less than $900 million.

And there are more growth opportunities for Trulieve as well. The company's expansion into California, Connecticut, and Massachusetts should enable Trulieve to boost sales. There's even a chance that Florida could legalize recreational marijuana, with efforts underway to place a constitutional amendment to do so on the state's ballot in 2020. Recent polls show that 67% of Floridians support legalizing pot. If Florida follows in the footsteps of the 11 other states that have legalized recreational marijuana, Trulieve will have a significantly larger opportunity.