Re:In Investing, It’s When You Start and When You Finish (2011)
by sokoloff on Monday October 17, 2016 @07:05PM
(#12730640)
That's true iff the 529 plan money is "required" for college. If you take instead the view that the 529 plan is just one type of asset that your child has, that you are optimizing for lifetime returns, and that attending vs not attending college is not changed by the 529 returns, then you could take the view that the 529 funds are just as subject to optimal asset allocation as any IRA or brokerage investments the child might have.
Though my kids are 5 and 7, I plan to invest on their behalf in 529, UTMA, and other accounts with their anticipated lifespan as the controlling factor, not which moment I expect to need the funds (because it is overwhelmingly likely that there will be other funds available if needed).
Depending on the age of your son, you may really want to consider investing in more stable assets. 20 years is a typically considered a minimum time-horizon for being heavily-weighted in stocks due to their volatility. If your son is older than 5, preservation of the earnings you've already made should start to become a significantly higher priority than high returns.