Despite several huge new markets opening up in 2018, last year ended up being a disappointment for many marijuana stock investors. However, 2019 could bring better news as those markets mature and grow and even more new marijuana markets open for business.

Which marijuana stocks are poised to win in the new year? Constellation Brands (NYSE:STZ), Innovative Industrial Properties (NYSE:IIPR), Origin House (NASDAQOTH:ORHOF), KushCo Holdings (NASDAQOTH:KSHB), and Charlotte's Web Holdings (NASDAQOTH:CWBHF) appear to be great marijuana stocks to buy in 2019. Here's what makes these stocks stand out.

Marijuana leaf on top of $100 bills.

Image source: Getty Images.

1. Constellation Brands

Alcoholic beverage maker Constellation Brands made big news in 2018 with its big bet on Canopy Growth. I think that that bet will begin to pay off this year as the Canadian recreational marijuana market grows, especially with the anticipated finalization of regulations relating to cannabis-infused beverages.

While the Canopy Growth connection lands Constellation a spot as a marijuana stock, its core business is still the main reason to like this stock. Constellation reigns at the top of the U.S. premium beer market with strong brands including Corona and Modelo and beer operating margins at record highs in the last quarter. The company's launch of Corona Premier, the first major addition to the Corona franchise in nearly three decades, is already a tremendous success and should help drive more growth for Constellation in 2019.

Check out the latest Constellation Brands earnings call transcript.

2. Innovative Industrial Properties

Innovative Industrial Properties operates as a real estate investment trust (REIT) and focuses on the medical cannabis industry. The company's revenue soared 150% in the third quarter of 2018. Innovative Industrial Properties also posted a healthy profit and paid its sixth consecutive quarterly dividend, with its dividend yield currently north of 3%.

I expect more growth, more profits, and more dividends in 2019. Innovative Industrial Properties owned 10 properties in eight states as of November 2018. A recent acquisition of a property in Illinois will boost those numbers. The company should continue to reap the rewards from expansion in the states in which it currently operates and by moving into more of the 31 states that have legalized medical marijuana.

Check out the latest Innovative Industrial Properties earnings call transcript.

3. Origin House

California is the biggest legal marijuana market in the world. And Origin House is the biggest distributor of marijuana products in California. The stock jumped nearly 60% in 2018 while many marijuana stocks floundered. I expect the rising tide in California to lift Origin House even more in 2019.

It's important to note that California's launch of its recreational marijuana market last year wasn't as successful as expected. But as the state fixes some of its issues and licenses more dispensaries, Origin House should benefit. In addition, the company continues to launch more of its own brands as its distribution business grows. I think that the combination of these factors should make this stock a winner for the second year in a row.

4. KushCo Holdings

KushCo Holdings has established itself as the top supplier of packaging solutions to the U.S. cannabis industry. As a result, the company should prosper as marijuana sales in the U.S. climb. That seems inevitable, with the U.S. marijuana market projected to soar to more than $22 billion by 2022.

But KushCo's growth prospects aren't limited to just the U.S. or to just packaging solutions. The company plans to expand into Canada and Europe. KushCo also has made several acquisitions that position the company in other parts of the cannabis supply chain, notably including supplying the cannabis industry with hydrocarbons and solvents for extracting cannabinoids and providing marketing services to the cannabis industry.

5. Charlotte's Web Holdings

One of the biggest marijuana-related stories in the final weeks of 2018 was the U.S. legalization of hemp, which by definition is cannabis that contains low levels of psychoactive compound THC. And one of the biggest beneficiaries of this legalization is Charlotte's Web.

The company already claims the top market share for hemp-based cannabidiol (CBD) wellness products. Charlotte's Web is likely to significantly increase the number of retail stores that carry its products in 2019 -- and boost revenue in the process -- thanks to the legalization of hemp in the U.S. Estimates vary on how big the U.S. hemp-based CBD market will be, but if cannabis market research company Brightfield Group's projection of $22 billion by 2022 is even in the ballpark, Charlotte's Web stock should have a lot of room to run.

Risks

It's only fair that I point out the risks for each of these stocks. Murphy's Law -- anything that can go wrong will go wrong -- can apply to the marijuana industry as much as it does anywhere else.

Probably the biggest concern is that an overall stock market correction (like the one we've seen in recent months) could pull all five of these stocks down. There's always the possibility that the anticipated growth for marijuana and hemp sales won't pan out like many expect it will. Charlotte's Web also still faces potential roadblocks from the U.S. Food and Drug Administration (FDA), which oversees regulations for CBD products.

But there are always risks with investing. My view is that the prospects for Constellation Brands, Innovative Industrial Properties, Origin House, KushCo, and Charlotte's Web make these five marijuana stocks top picks for aggressive investors.