Advisors, don’t let your clients’ babies grow up without a college savings plan.

The question becomes: How should clients prepare for this cost? There are two ways, but both follow a similar logic, according to Christine Benz, Morningstar director of personal finance, in her column, How to Allocate Assets for College Savings.

The method of saving for college is different than for retirement, Benz notes. Mainly because a person can save for more than 40 years for retirement, while saving for college typically involves half the tie frame and a much faster drawdown (four years and maybe grad school).

There also is the problem with a bear market during the college buildup, which can take a big bite out of savings if they aren’t apportioned correctly. Retirees may have some wiggle room while college-bound kids may not. As Benz notes, “Try telling your 18-year-old that he’ll have to wait until age 21 to start school so that his college fund will have time to recover.”

Therefore, college savings funds have a much “steeper glide path — the gradual shift from more volatile investments such as stock to more conservative investments such as bonds — in leading up to and during college than the typical glide path before and during retirement,” she writes.

In fact, the timeline is fast and furious: accordingly, when a child is age 0 to 6, the mix in a portfolio — roughly — should be 72% U.S. and foreign stocks, 24% bonds and 2% cash. The stock mixture begins dropping after age 6, while bond holdings grow. From ages 7 to 12, stocks holdings should drop to 52% of the portfolio while bonds come up to 41% and cash is 4%.

Ages 13 to 18 should see a stock mix of 29% and bond holdings of 56% and cash growing to 9%. After 19 (and assuming the child is in college), stocks should downshift to 17%, bonds 60% and cash 17%.

“College savers must strike a tricky balance because the risks of being too conservative also loom large,” Benz says. “Inflation is a major foe for college savers, and a portfolio heavy in bonds and cash could have trouble keeping up with rising tuition costs.” Inflation for college costs has been running about 5% over the past decade, she adds.

If clients (or the advisor) don’t want to manage the college savings themselves, another option is investing in 529 plans, which do the investing for clients and usually come with a tax benefit (as long as it goes to college expenses, money isn’t taxed). Although most states have plans, a client can invest in some other state plans. Morningstar just ranked the best and worst 529 plans.

Obviously, clients can decide to save on their own or go with a 529 plan, but Benz notes that “given the specific considerations that should go into a college savings allocation plan, it’s probably no wonder that the age-based options with 529 college savings plans have historically held the lion’s share of assets.”

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