MANHATTAN, Kan. – Appearances can be deceiving. From the turf’s view, for example, people with pristine landscapes and those with poorly kept yards can both be practicing cruelty to lawns.

Late spring is transition time for tall fescue and Kentucky bluegrass — Kansans’ hands-down favorite lawn turfs, said Matt Fagerness, horticulturist at Kansas State University.

If fescue or bluegrass ends spring looking like a plush green carpet, it may be unprepared for summer’s stresses, he said. If either turf looks uncut and uncared for, it also may be unprepared.

"You can’t take it back, if you made the mistake of overfeeding your lawn this spring," Fagerness said. "You can’t make it up, if you forgot to apply preventer before the crabgrass sprouted.

"But you can start training your lawn to be tougher, so you and it both have a better chance of surviving this summer in good shape."

This tough love has two parts:

1. Give your lawn the water it needs. But make the grass work for it.

2. Trim, don’t scalp or hack when you mow.

In most years and most soils, the weather provides enough rain to irrigate lawns in spring, said Fagerness, who is K-State Research and Extension’s turfgrass specialist.

So, Kansans who’ve already hauled out the sprinkler may actually be "spoiling" their lawn.

"Frequent, shallow waterings are the worst. Turf may look okay above-ground. But the roots end up in just the top inch or two of soil. As a result, two or three hot, dry summer days can affect that root system like a blow dryer set on high," he said.

About once a week through the growing season, fescue and bluegrass need enough water for their soil base to get moist to a depth of 6 inches. This encourages the deep root growth that helps them survive adverse weather conditions, Fagerness said. Infrequent, but deep watering (or rains) achieves this best.

"The only way to know if the soil really has that much moisture is to look. Rain gauges and weather forecasters can’t measure what’s happened in every part of your yard," he said.

Some homeowners use a spade to examine cuts made into lawn and soil -- which they foot-pressure back into place. Fagerness prefers pushing a long screwdriver into the ground. A screwdriver or similar metal rod stops moving when it hits dry dirt, thereby indicating how deep the moisture goes.

"If you’re irrigating, do this in several places. Sprinklers can really range in how evenly they distribute water," he advised. "During hot spells and in areas where the soil is sandy, check fairly often. Under those conditions, you may need to be watering more than once a week."

Lawns with care-less owners can enter summertime in fair condition. Fescue and bluegrass are cool-season turfs that thrive in spring and fall.

If they don’t receive water during summer, however, these lawns may die. Or, they may become dormant and wheat-colored, while weeds and weedy warm-season grasses do their best to take over.

In much the same way, mowing too much and too little can hurt turf.

"If you’ve been mowing short this spring, to encourage the turf to thicken up, raise your mower height right now. A little of that approach is okay. But continuing it for very long tells the lawn it doesn’t need anything more than a short root system," Fagerness warned.

In contrast, repeatedly letting a lawn to grow too tall before mowing shocks the turf’s root system, he said. Plus, the lawn becomes thin and stemmy. It not only looks worse but also can lose weed- and weather-fighting ability.

The rule of thumb on mowing is never to remove more than one-third of the turf’s leaf height at any one time.

"In practical terms, that means you can let fescue get close to 5 inches tall before mowing, because its recommended height after cutting is 3 to 3.5 inches," the horticulturist said. "Bluegrass is even easier to figure. Its recommended after-cutting height is 2 to 2.5 inches. So, you know mowing time’s rolled around again when bluegrass gets 3 to 3.5 inches tall."

Occasionally letting grass grow too long won’t kill it.

"I certainly wouldn’t give up plans to go to Disney World so I could stay home and mow the grass," Fagerness said. "But when you get back home, remember the one-third rule. And remember your cool-season turf will already be under stress, just because it’s summertime. Adjust your mower height over two or three cuttings, so you can gradually take lawn height back to where it needs to be."