MANHATTAN, Kan. -- With luck and early planting, Kansas gardeners could celebrate July 4 this year by serving baked potatoes that are red inside. Or white. Or blue. Or yellow-gold.

"The new red and blue varieties are still difficult to find outside of catalogs," said Kansas State University horticulturist Chuck Marr. "But, a number of garden centers plan to carry yellow-fleshed, as well as white-fleshed seed potatoes this year.

"A good yellow in Kansas, for example, is Yukon Gold. It carries its buttery-looking color through any cooking process and even provides a little more Vitamin A than standard potatoes do."

The red and blue varieties on the market now are much less productive than standard white-fleshed potatoes, he added. They also may tend to lose pigment when boiled. So, retaining their unusual color could mean firing up the microwave or oven.

Long, narrow "fingerling" potato varieties are another fairly new offering for 2001.

"But, fingerlings mostly are not very productive in Kansas. They’d be your last choice if you want to grow a year’s supply," Marr warned. "The traditional white potatoes with white, red or russet skins are still the most productive. Kansans can get some good yields from yellow varieties, too. The blues and reds produce less well, but they’ll still beat the fingerlings."

Traditional potato-planting time through much of the Midwest is in March on St. Patrick’s Day.

"So, if you want to try something unusual this year, you’d better start selecting your seed potato source right now," the horticulturist said. "Look for a place that sells only inspected and guaranteed disease-free stock. In the store, that kind of stock will have a blue tag on the bag."

Marr, who is the vegetable crops specialist for K-State Research and Extension, also recommends these planting steps -- for all hues of potatoes:

* Use only firm, solid tubers you bought this year. Using potatoes saved from last year’s garden causes yield and vigor loss.

* Cut into pieces, each of which contains at least several "eyes." Average-size potatoes usually yield four pieces; large potatoes, six.

* Store the cut pieces in a warm, humid place for two to three days, to allow the cut surfaces to "heal." (This prevents rotting after planting.)

* Pick a fertile, well-drained planting site with loose, friable soil.

* Plant the potato "seeds" 12 inches apart in rows that are 3 feet apart. Bury less than 2 inches deep. (July-planted potatoes for a fall harvest must be 4 to 5 inches deep.)

* Provide regular, consistent watering.

* As the seedlings grow, pull loose soil from between rows and mound it around the plants to gradually start creating a hill (ridge). Eventually, each hill-row should be 8 to 12 inches high. (Ridging helps prevent sunburn and increase yields.)

* Harvest early or new potatoes as needed, being careful to protect their tender skin.

* Wait to dig mature potatoes until the vines are half-dead.

"Potatoes take some room, but can be surprisingly easy to grow," Marr said. "Nowadays, they can be a fairly colorful crop, too ... at least by the time they reach the table."

His in-depth publication on growing, harvesting and storing Irish potatoes is available at every Kansas county Extension office and on the Web (http://www.oznet.ksu.edu/library/hort2/vegetabl.htm).