The kitchen can be a place of fun and learning when the indoor gardener plants some of the seeds and roots remaining from daily meal preparation.

Some recycled left-overs give speedy results; excitement grows while you wait for plants to sprout. Others are slow and stubborn, or may not respond at all. With some, it helps to know the natural environment of the plant. For instance, tropical fruit seeds appreciate extra warmth and humidity to get off to a good start; others require special treatment before planting.

For an "almost instant" small foliage plant, cut an inch or two from the top of a carrot; set the stump in a shallow container with just a little water; the addition of pebbles or sand will help hold it steady. Remmber to replenish the water as it evaporates.

In a couple of days you will have a dish of eye-refreshing greenery. Carrot tops are filmy, light green fronds. Others to try are turnips and beets. Turnip greens are not as feathery as carrots - more substantial looking. Beets produce glossy green leaves with red veins.

Besides the ubiquitous favorite, the avocado, other seeds from the kitchen also can be grown as houseplants.

Seeds of citrus fruits, such as grapefruit, orange, lemon and lime, germinate easily and become small trees with glossy dark green foliage. Select plump seeds and wash them. Plant several seeds per pot in general purpose potting soil and water them. Cover the container with aa plastic bag and keep it warm. When seeds sprout remove the cover and place them in bright light. Remove all but the sturdiest from the pot if you prefer to have just one plant grow to some size.

Although citrus plants are slow growers and may never produce fruit, they are attractive houseplants.

If you are endowed with patience, try planting date pits. Seeds from non-pasteurized dates (check the package label) can be planted in any potting soil. Plant them an inch deep in a deep pot to provide lots of root room. They are slow to sprout but will produce small palm trees that can be kept as pot plants for some time. One veteran seed saver and experimenter planted her dates in a pot with other large plants and moved them to individual pots when they reached transplant size.

Apple seeds need special treatment to induce germination. Store the seeds in a mixture of peat moss and sand in a plastic bag in the food compartment of the refrigerator (about 40 degrees) for two or three months, then plant them. Apple seeds take about a month to germinate. Grow the seedlings in 4 inch pots.

Apples need to be wintered outdoors. If you can make provision for the alternatind seasons o winter and summer, you can keep the plant growing as a small tree for some time.

Many food chains and neighborhood markets regularly offer "ethnic foods," i.e., food from other cultures, not familiar to the American dinner table. Among these is ginger, a tropical Asian plant in which the underground stem is used in Asian dishes.

Select a piece of ginger root form the fresh produce section of grocery. Choose a shallow, wide pot, large enough to accomodate the piece of ginger. Fill the pot three-quarters full of general purpose potting soil; set the ginger root and barely cover it with soil. Keep the soil moist. It will speed sprouting if you can provide some heat from the bottom, for instance by setting the pot on several layers of newspapers on a radiator or but setting on an electric tray used to keep food warm.

When growth starts move the pot to a bright location. A good piece of ginger should continue to sprout for several months, giving you a plant that somewhat resembles bamboo.

If you keep a supply of Jiffy-7 peat pellets on hand, you are ready to go into action as soon as any seed becomes available and stirs your imagination as a potential bit of kitchen greenery. All you have to do is place the peat pellets in a shallow container, add water according to package directions and plant your seeds. Keep the pellet moist and warm as required for the seed you've planted. When seeds have sprouted and filled the pellet with roots, the whole thing can be planted in a pot of an appropriate size.

Your own ingenuity will lead you to try seeds or plant parts I have not mentioned, for instance, papayas, peaches, sugar can. The plants are nice, even if you never pick a date, orange or apple. Where young inquisitive minds are at work, learning is fostered at no expense through such gardening activities.

Have fun with your kitchen castaways.