The re-greening of downtown Kansas City is off to an encouraging start, as we noted in The Star on Sunday. But further improvements are still needed.

One major challenge is to upgrade Grand Boulevard north of the freeway loop. Substantial progress has occurred in the last year as new trees, shrubs and other landscaping were placed at the Sprint Center and the Power & Light District.

But for many blocks north toward the River Market, Grand Boulevard — with wide sidewalks and many small or dead trees — still has an empty, depressing feel.

Part of the problem: Underground vaults beneath the sidewalks along Grand make it difficult and costly to plant trees and shrubs. The city should find ways to get around that problem, with the cooperation of businesses that line the street. Surface planters, properly done with the right size of tree, could help.

The failure to plant anything at all north of the College Basketball Experience has left a vast expanse of wall — next to a nearly 10-foot-wide sidewalk — greeting visitors to the Sprint Center and the Power & Light District.

City Hall ought to do a better job working with private businesses as well as the Downtown Council to make downtown more attractive. Meanwhile, many side streets off Wyandotte, Baltimore, Main and Walnut still look bleak, lacking much greenery at all.

City officials paid for a consultant’s extensive report on how to improve downtown’s landscaping. While strides have been made to follow that plan, the city should invest additional public dollars into streetscape improvements that will pay big dividends for many years to come.