Our favorite holding period is forever. -- Warren Buffett

Forever is an awfully long time. Heck, the average holding period for stocks isn't even one year anymore, since the advent of online trading, computer-driven high-speed trading, and steadily falling brokerage costs. But even with so much of a shift toward short-term trading, the most effective way for individual investors to get the best returns remains the simplest: Buy great companies, and hold them as long as possible. 

Owning stocks that pay a dividend can make it much easier to hold on to them, particularly if they have the ability to steadily increase the payout and solid prospects to grow the business. To help find the best long-term dividend stocks out there, we asked three of our Motley Fool investors for a little help. They came back with Gaming and Leisure Properties Inc (GLPI -0.54%)AES Corp (AES 0.05%), and Caretrust REIT Inc (CTRE -0.04%)

Seedlings getting progressively bigger.

Image source: Getty Images.

What sets these three apart as decade-beating dividend investments? They all operate businesses that generate predictable, steady cash flows well in excess of their dividends, while also having solid prospects for years of growth ahead. 

A bet on future gaming growth

Rich Duprey (Gaming and Leisure Properties): As the first real estate investment trust to focus on the casino industry, Gaming and Leisure Properties has staked out a unique position that will allow it to capitalize on the growth of gaming in areas away from the spotlight of Las Vegas and Atlantic City. Places like Perryville, Md., may not be spots where people first think about casinos, but it's in out-of-the-way places like that where regional gaming operators are making their mark.

Formed by Penn National Gaming to own the real estate while it operated the casinos, Gaming and Leisure has become the third-largest publicly traded triple-net REIT, which means the tenants, in this case the actual casino operators, agree to pay all real estate taxes, building insurance, and maintenance on the properties. And like other REITs, it pays out most of its profit to investors in the form of dividends. Its dividend yields 7.3%.

The real benefit to investing in the REIT comes from the improving quality of the tenants of the properties it manages, and because this niche of the gaming and REIT market is still relatively new, as investors become more knowledgeable about it they'll see it has a durable and predictable revenue stream with a healthy moat to protect it from competition.

With existing relationships with both Penn and Boyd Gaming, the two largest regional casino companies in the market, Gaming and Leisure Properties has a pipeline for future additions to its portfolio. Ten years down the road, this is one stock you'll wish you would have bought.

A small utility with big growth potential

Neha Chamaria (AES Corp): You might not be familiar with AES Corp because it's still a relatively smaller power-generating company in an industry chock-a-block with big names. Yet, I find AES to be a pretty interesting utility given its commitment to shareholders and the way it's transforming its portfolio.

AES is doing a whole lot of things right now, the prominent one being its shift to renewable energy. So in 2017, the company divested 4.3 gigawatt (or roughly 4,322 megawatt), or 37% of its total coal-fired capacity. At the same time, it added 2.3 GW of renewable energy to its portfolio, primarily solar and wind, through acquisitions. By 2021, AES expects to bring another 4.4 GW of clean energy capacity online, thereby adding nearly 6.6 GW of new clean-energy capacity over the next two to three years.

Meanwhile, AES is using proceeds from the sale of its non-core assets to pare down debt -- a move that already recently won the company a ratings upgrade from credit rating agency S&P Global Ratings. AES believes its ongoing efforts to expand its renewable-energy capacity, deleverage, and cut costs should help the company grow adjusted earnings per share and free cash flow each by 8%-10% annually through 2020.

That should also mean higher dividends for investors, given that AES has increased its dividend every year since 2012. In fact, AES' absolute annual dividend amount grew from just $0.16 per share in 2013 to $0.48 per share in 2017, reflecting management's intent to share a greater portion of incremental free cash flows with shareholders. With the stock yielding an attractive 4.2% today, income investors might regret not owning this stock a decade from now.

This multidecade trend should drive big growth

Jason Hall (Caretrust REIT): Between 2010 and 2029, the number of Americans over 65 will double to 80 million, and by 2035, 20% of the U.S. population will be 65 or over. Factor in increasing life expectancies, and the 80-plus population is also rising sharply. This puts Caretrust squarely in the middle of a big-picture need to steadily expand our capacity to care for older Americans in the decades ahead. 

Two factors have been working against Caretrust recently. The first is an oversupply of nursing homes, as more in-home services, better preventive care, and increased efforts by policymakers and families has steadily reduced the percentage of seniors who end up in nursing homes. Second, rising interest rates have caused many investors to sell out of and to avoid investing in real estate investment trusts -- REITs -- like Caretrust out of concern that they will suffer from higher debt costs. 

And while these are concerns, I think it's been overplayed and created an opportunity for true long-term investors. With a high-quality management team that's proven to be great with capital allocation, the bigger trend above should give Caretrust a much bigger tailwind than any challenges rising rates could create. Caretrust also trades in value territory. Its dividend yields 5.2% at recent prices, and only requires 64% of funds from operations to cover, giving it a substantial margin of safety, while shares trade for less than 13 times management's guidance for normalized full-year FFO. 

Between its fair value, margin of safety for the dividend, and great growth prospects, Caretrust could create enormous wealth for investors over the next decade and then some.