“Do now or don’t do” time has arrived for central U.S. residents who work in their yard and garden.

“June 1 is typically a good deadline to be finished with any spring plantings–annuals, perennials, shrubs and trees,” said Emily Nolting, horticulturist with Kansas State University Research and Extension. “Of course, planting can continue well into June. But, the general recommendation is that the later it gets into the season, the more you’ll need to use larger and often more expensive plants.”

Planting before hot weather sets in helps plants get a better, faster start, she explained.

In addition to warm-season annual flowers, the late-May planting deadline can include the warm-season vegetables–tomatoes, hot and bell peppers, and eggplant (purchased transplants), as well as sweet corn, green beans, cucumbers and summer squash (from seed).

“If you use a good potting mix, you can plant some of those annuals in container gardens and hanging baskets,” Nolting said. “Just don’t suspend baskets from the overhang of your roof. They’ll never get rain there, but will be baking in about the hottest environment you could provide.”

Moving and dividing most perennials should be okay until the end of May, she said. The exceptions are irises and peonies, which prefer being moved and/or divided in August and September.

“You’ll have to watch these late transplants as they adjust, to see if they need extra care,” Nolting added. “The reason pros advise dividing and moving perennials earlier is simply that that way, the plants have time to adjust while it’s still cool and often rainier, so adjusting is easier.”

Trees and shrubs planted at any time during spring will require extra care throughout their first growing season, the horticulturist said. If rainfalls aren’t timely, new ornamental plantings will need deep watering once a week through summer to help their slowly growing roots become firmly established.

“If sapling trees are someplace that gets a lot of wind, staking can be a good idea for the first season,” she said. “Just make sure no wire can cut into the tree. Then remove the stake next spring.”

Nolting advises against moving existing ornamentals, however, this late in the season.

“It’s always best to dig them up before they’re completely out of winter dormancy. The earlier in spring, the better–especially if the plant is large,” she said.

June 1 also is the deadline for having finished any needed pruning, Nolting said. That could mean removing dead or freeze-damaged wood or shaping spring-flowering shrubs that have finished blooming.

“Get ready to spray for bagworms, too. If you had them last year, they’ll be back. June 1 to 15 is the best time to get a complete kill, while this year’s generation is tiny and mostly unprotected,” she said.

June 1 is an equally handy deadline for mulching all landscape plants, including those in containers and baskets. These plants didn’t really need insulation earlier, but mulching now will help prevent splashing, retain water, prevent erosion, keep soil cooler than the air, and discourage weeds.

“The finer the mulch, the less you need,” she said. “An inch of peat moss is enough to provide a good cover, yet not so much that it’ll mat and repel water. With big bark mulch pieces, you’ll need from 3 to 4 or 5 inches. For the typical cypress mulch, about 2 inches deep is just right.

“Spread your mulch over any bare ground except the couple of inches right next to where a plant is growing or where you’ve got a building foundation and want to discourage termites. Covering a perennial’s growing point or crown will cause problems. Creating an organic mulch volcano that’s way up on a sapling’s trunk can eventually kill the tree.”

Any time in May, however, is none too soon to start weaning the region’s favorite lawn turfs–tall fescue and Kentucky bluegrass–from wanting a constant supply of water.

“This spring’s weather isn’t making that easy,” Nolting said. “But, you should be irrigating only after these lawns are showing stress because they really need water. They’ve got to learn to get by on less–unless, of course, you plan to struggle to keep those lawns lush, green and growing all summer long.

“That’s a challenge that takes lots of work and hefty water bills. If summer’s weather gets bad, you may have to water up to twice a day, just to keep a lush lawn from going dormant–or worse.”

Waiting until early summer to wean cool-season grasses from their dependency on excessive moisture levels can be a recipe for losing a lawn to hot, dry weather, she warned.

If weaned at the right time, though, these turfs often need no supplemental water until sometime in June. They’re finally thirsty enough when they turn a dry blue-green and retain the shape of footprints.

“But make sure your mower is at the upper end of the recommended cutting range now. For fescue and bluegrass, that’s 3 to 3.5 inches high,” Nolting said. “Mowing shorter than that encourages weed growth and stresses the plants. At their recommended height, grass blades can shade and insulate their growing zone and help conserve water–another plus when summer weather arrives.”

More information on landscapes and gardening is available at any local K-State Research and Extension office, as well as on the organization’s website at www.oznet.ksu.edu.

source : www.hpj.com