Our Motley Fool contributors think sales and profit growth at Starbucks (SBUX 0.61%), Lockheed Martin (LMT -1.04%), and Intuitive Surgical (ISRG -1.83%) make them envy-inspiring additions to long-term portfolios. Are these stocks right for your retirement account? Read on to find out.

A sustained buzz for your long-term portfolio

Seth McNew (Starbucks): Already one of the most powerful brands in the world, but with plenty of growth opportunity ahead, Starbucks continues to look like a great long-term bet. The coffee behemoth is not without its own risks and competitive pressures, but its international expansion efforts and industry-leading technology should provide a steady growth runway.

A cup of coffee sitting next to a pile of coffee beans.

IMAGE SOURCE: GETTY IMAGES.

Starbucks' same-stores sales have been sluggish lately, dragged down by slow growth in North America. In the recently reported fiscal Q2, same-store sales companywide grew just 3% year over year. However, the company continues to expand its footprint, adding more than 1,000 new stores in the last two quarters to now over 26,000 worldwide. Management sees room for another 12,000 locations worldwide by 2021.

In addition, Starbucks continues to find ways to innovate, such as with its mobile strategy and the new premium Reserve stores, that should help to increase ticket prices and profit margins. The stock still isn't cheap, as shares trade at about 25 times next year's estimated earnings, but that gets you a company that has historically commanded a high valuation, pays a healthy and growing dividend, and appears to have set the stage for stable long-term gains -- a great growth stock for retirement.  

A great "defensive" investment for your retirement portfolio

Rich Smith (Lockheed Martin): Ordinarily, growth stocks aren't what I look for in a stock for retirement. Stable income and sustainable dividends seem more appropriate objectives to me. But opinions differ, and with Americans living longer and longer in retirement these days, maybe it is time to start thinking about growth stocks as a good investment for retirement.

A C-130 airplane on a runway.

IMAGE SOURCE: LOCKHEED MARTIN

After all, with many Americans able to retire as early as age 62, and the average life expectancy now pushing 79 (or more!), there's every possibility that an investment purchased at the start of a retirement will have a couple of decades in which to grow throughout retirement.

So what's a good stock to buy today, with the expectation of holding onto it and watching it grow over the next 20 years or so? My vote goes to Lockheed Martin -- a business I'm 100% certain will still be around 20 years from now.

Why Lockheed? Well, consider the facts. The nation's largest defense company, Lockheed Martin produces the best-selling fighter jets (the F-16 Falcon), the best-selling military transports (the C-130), and the best-selling military helicopters (the Black Hawk) in the world. Each of these aircraft is built with the expectation that it will fly for decades, not years, and over the lifespan of each aircraft, Lockheed Martin will be the company providing maintenance, upgrades, and other services to keep the aircraft functioning. There's no doubt in my mind, therefore, that the company building these aircraft will still be earning profits from them 20 years from now.

And that's before we even begin to consider the impact of Lockheed Martin's F-35 franchise -- which the top brass at the Pentagon tell us is probably the last manned fighter jet the U.S. will ever develop. The U.S. military plans to buy literally thousands of these fifth-generation jets over the next 60 years, and Lockheed has zero competition to contend with in selling them -- because no one but Lockheed even builds a fifth-generation fighter jet.

With 60 years of profitable growth from the F-35 ahead of it, Lockheed looks to me like a great growth stock for anyone planning for retirement -- no matter how long life expediencies get in the years ahead.

Rely on robotics

Todd Campbell (Intuitive Surgical): Certainly, owning dividend-paying stocks with low price-to-earnings ratios in retirement accounts makes sense, but if you're looking for a little extra pop in your retirement account, then Intuitive Surgical could be a perfect stock to buy.

Unfamiliar with Intuitive Surgical? Here's the elevator pitch: Intuitive Surgical is the market-leading manufacturer of robotic-surgery systems (by leaps and bounds); its systems are already a staple in mid- and large-sized hospitals worldwide; it has a profit-friendly business model that benefits from high-margin disposable instruments and accessory sales; and it has a lot of opportunity to expand into additional surgical indications.

Globally, there are over 3,900 da Vinci systems in use, and while these systems cost nearly $1.5 million, a lot of Intuitive Surgical's profit is coming not from system sales, but from the selling of instruments and accessories that have to be thrown out after every procedure. On average, every machine sold generates $1,840 in consumable sales per procedure, and last year, 752,000 procedures were done on da Vinci's. In Q1, the number of procedures performed increased 18% year over year, and as a result, instrument and accessory sales now represent 56.5% of revenue, up from 46% only two years ago.

All those installed systems means the company also makes a lot of money from service contracts too. In Q1, service revenue totaled $140 million, and that was only a little shy of the $153 million it booked in da Vinci system sales.

Importantly, procedure volume may have a lot of room to continue growing. The da Vinci system is commonly used in prostate and OB/GYN procedures, but it's only now gaining widespread adoption in general surgery, such as hernia repair. As da Vinci wins use in multiple indications, additional systems should produce even more in high-margin consumable sales.

Overall, Intuitive Surgical shouldn't be the only stock owned in a retirement account, but if you want to add a growth stock to a diversified portfolio, then this is a company worth considering.