Buying and holding high-quality growth stocks is one of the best ways to predictably generate wealth over the long term. But finding the market's best growth stocks is easier said than done.

To that end, investors need to be able to recognize opportunities before the rest of the world catches on. So we asked three top Motley Fool investors to each pick a growth stock that they believe forward-looking investors can appreciate today. Read on to learn why they chose Splunk (SPLK)Portola Pharmaceuticals (PTLA), and Scotts Miracle-Gro (SMG 1.72%).

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Image source: Getty Images.

Making sense of the nonsensical

Steve Symington (Splunk): I've watched Splunk for years as it emerged the top operational intelligence platform on the market, helping its nearly 14,000 customers make sense out of their growing mounds of unstructured machine data. So I was elated when I got the chance to travel to Splunk's San Francisco headquarters last week to talk about their recent integration of artificial intelligence and machine-learning tools across their portfolio of products. 

One thing that shined through in that meeting was Splunk's insistence that they still enjoy a "high ceiling" for growth despite their recent success.

To be sure, even though Splunk already counts 85 members of the Fortune 100 among its clients, and reached $1.2 billion in revenue last year alone, its growth is only just beginning. The company estimates its total addressable market currently stands at $55 billion, which would mean expanding to between 300,000 and 400,000 customers in the coming years. 

For investors willing to bet that Splunk will steadily grow its share of that market, and even with shares up 76% over the past year as of this writing, I think Splunk is a winner that will keep on winning.

Down, but not out

Brian Feroldi (Portola Pharmaceuticals): 2018 was supposed to be a breakout year for Portola Pharmaceuticals. Bevyxxa, which is the company's anticoagulant that was just launched in January, looks poised for fast growth. Meanwhile, a potential blockbuster drug called AndexXa is set to hear a go/no-go decision from the FDA in early May. The thumbs up on AndexXa would most certainly cause shares to soar. 

Unfortunately, the year isn't exactly coming together the way that investors had hoped. Portola's shares were recently slammed after investors learned that AndexXa's approval timeline might have to be expended. On its most recent conference call with investors management stated that European and American regulators have requested additional data to support their approval decision. The move is expected to delay an announcement in Europe until the back half of this year. It is possible that the company's PDUFA date of May 4 may be delayed, too.

While a potential AndexXa delay is certainly not good news, I still believe that the odds of an eventual approval are favorable. What's more, you could argue that the company's current market capitalization of $2 billion is justified based on Bevyxxa's sales potential alone. If I'm right then Portola's stock represents a great buy right now for investors who can take the long-view.

Increased focus and an awesome growth opportunity

Maxx Chatsko (Scotts Miracle-Gro): As you can probably imagine, the home gardening industry in North America is highly seasonal. Unless you own a greenhouse, your green thumb is probably covered by warm gloves during the colder winter months. While that has resulted in revenue and earnings being incredibly lumpy during certain quarterly periods, it hasn't really affected the performance of Scotts Miracle-Gro stock over the years. In fact, shares are up 139% in the last five years including dividend payments, well above the 95% total returns of the S&P 500.

Nonetheless, years ago management moved to smooth out some of the seasonality in its business by acquiring a hydroponics and indoor gardening company called Hawthorne. A continuous stream of acquisitions in the space have bolstered the Hawthorne segment since, and the emerging opportunity in legalized marijuana has certainly helped, too. The result: Scotts Miracle-Gro generated 10.8% of total revenue from its hydroponics unit in fiscal 2017, compared to just 4.8% in fiscal 2016. 

In other words, in addition to providing non-seasonal revenue, Hawthorne provides a high-growth opportunity with plenty of potential for the foreseeable future. That provides a great one-two punch for Scotts Miracle-Gro. After all, the core business is still providing leading brands to the consumer gardening market. That includes Scotts, TomCat, Roundup, and many others -- most of which have an impressive track record of delivering organic growth to shareholders. Throw in strategic investments in and partnerships with craft brands, such as Bonnie Plants, and it's clear the core business is no slouch.

After divesting all business units outside of North America (which contributed declining revenue and had lower margins), Scotts Miracle-Gro can now focus all of its bandwidth and resources on its most important opportunities. So long as the company can continue growing earnings and cash flow, then it should be able to continue providing above-average growth for investors.

The bottom line

There's no way to absolutely guarantee that these three stocks will beat the market over the long run. But whether we're talking about Splunk's massive addressable market, Portola Pharmaceuticals' seemingly temporary setbacks, or Scotts Miracle-Gro's renewed business focus, each company enjoys a unique advantage that could mean enormous gains for investors ready to seize the opportunity.