Sometimes, getting those five to nine daily servings of fruits and vegetables into a diet seems daunting. And to those whose vegetable repertoire is limited to the basic beans, peas, carrots and corn, it might seem impossible. Just how many cups of peas can one person eat in a day, anyway?Farmers’ markets are overflowing with the greens and root crops of late spring and early summer. And tucked in among the usual lettuce, spinach and broccoli, there are treasures that may not be as familiar to some consumers. Vegetables such as Swiss chard and kohlrabi can add variety to standard fare.Kohlrabi, originating from Eastern Europe, is a member of the cabbage family. It has a thickened stem resembling an aboveground turnip. Smaller stems with leaves protrude from the top of the thick center stem. Both leaves and stems of the plant are edible. The stem can be entirely white, or green or purple with a white center. Jackie Walters, University of Kentucky Cooperative Extension family and consumer sciences specialist, said that kohlrabi can be a wise vegetable choice during the hot summer months since it is a good source of potassium.“Potassium is necessary for regulating water, blood pressure and muscle contraction,” she said. “It is especially important to get adequate potassium during hot weather, to prevent dehydration.”Besides potassium, kohlrabi is a potent source of vitamin C. Based on a 2,000 calorie diet, one cup of cooked, sliced kohlrabi provides 150 percent of the Reference Daily Intake or RDI (the current term for recommended daily value) of vitamin C.Chef Bob Perry, coordinator of the UK College of Agriculture Food Systems Initiative, said kohlrabi is a little sweeter and less pungent than a turnip. It can be peeled and sliced or shredded. Some people toss raw kohlrabi in a green salad. Perry also suggested sautéing it in butter and finishing it with cream, or cream and a little cheese. It can also be made into a dauphonise or gratin, like scalloped potatoes.“For a gratin, peel and slice very thinly,” Perry recommended. “Layer in a small buttered casserole. Mix heavy cream and salt together, pour over kohlrabi and press with your hands to distribute and level out veggies. The cream should taste salty and be not quite enough to cover the kohlrabi but ooze over the top when you press down. Bake covered for 30 minutes, then uncovered for 20 to 30 minutes in a 375 degree oven. Top with cheese and allow to melt. Enjoy.”Swiss chard gives you quite a lot of bang for your buck. Not only is it an attractive plant, with its large fanlike leaves and often-colorful, edible stems, it is a real nutritional powerhouse, according to Walters. A member of the beet family, chard is bred for its leaves, rather than its root. Some people compare its taste to spinach, while others think it displays a mixture of tastes similar to broccoli and mild radishes.A serving of cooked Swiss chard (two cups of raw, chopped Swiss chard before cooking) provides 90 percent of the RDI of vitamin A and 35 percent of vitamin C, again based on a 2,000 calorie diet.“This is a nutrition bargain, since it would only provide 15 calories,” Walters said. “Vitamin A is important for maintaining healthy eyes and skin and for disease resistance.”In addition, Swiss chard is very high in vitamin K, she said, which is required for the coagulation of blood.While the leaves of chard can be steamed like spinach or kale, Perry has an easy recommendation for using both stems and leaves. Strip the leaves from the stems, then slice the stems the same as celery. They can be sautéed in olive oil or butter, or blanched, which means to dunk them into boiling, salted water for a couple of minutes and then immediately dunk them into ice water to stop the cooking process.Repeat the previous step with the chopped leaves. Drain both the stems and the leaves. Put all the stems in the bottom of a small casserole dish.“What’s really good is if you have a little left-over something,” he said, “like roasted or grilled pork or chicken. You can slice or shred it and place it on top of the stems.”Next, make a basic white sauce with melted butter, flour, nutmeg and milk. Taking the drained, chopped leaves, mix with a little of the white sauce, and spread over the top of the stems. Finish it off by sprinkling cheese over the top. Either parmesan, asiago or gruyère cheese would work. Bake uncovered for 30 minutes at 350 degrees.For more fresh produce preparation ideas, contact a local Cooperative Extension office