Lesson plan by Kidsgardening.org
With little effort and a pinch of creativity you can devise some very imaginative indoor gardens from your kitchen leftovers! Kitchen scrap gardening is when you grow plants from items you'd normally throw in your compost bucket. Kids love this idea, and it's a great way to reinforce the sustainable living concepts of recycling and reusing. Plus, it's a kick to grow new plants from old plant parts.
Vegetable and fruit scraps (oranges, lemons, limes, sweet potatoes, avocados, carrots, beets, onions, and ginger work well)
Approximate Time to Complete: 30 minutes to plant, multiple days to grow
Ages: all ages
Season: all seasons
Scout your kitchen and refrigerator for potential vegetable and fruit candidates. Some of the best are oranges, lemons, limes, sweet potatoes, avocados, carrots, beets, onions, and ginger. Believe it or not, you can use all of these and many other vegetables and fruits to propagate new plants.
Plant scraps in potting soil or immerse in water. The best method for encouraging new growth will depend on the plant and plant part represented. Here are specific instructions for some easy to plant scraps:
Starting Little Seeds
Citrus fruits are plentiful in winter, and the seeds in oranges, lemons, grapefruit, and limes are easy to grow into new houseplants. Fill a 4-inch-diameter pot with moistened potting soil. Remove whole seeds from the fruit and plant three to four of them one inch deep in the pot. The seeds should sprout in two to four weeks and you'll have a mini citrus orchard. Keep the seedlings well watered for about six weeks and then transplant individual trees into bigger pots. It will be quite a while before you see citrus flowers (let alone fruit -- these trees won't bear for many years, and most eating-quality fruits are borne on grafted, not seed-grown trees.) But you can enjoy the leaves. The leaves smell like whatever type of citrus you're growing, so be sure your children do some "rub and sniff" tests.
Starting Big Seeds
If the small seeds are a hit, try growing big seeds of tropical fruits such as mango and avocado. Let an avocado pit dry out for a day or two, then plant it in a 6-inch-diameter plastic pot filled with moistened potting soil. Leave the tip of the pit exposed to air. Another fun -- and easy -- way to sprout an avocado is to suspend the pit over a glass of water. Poke three toothpicks around the middle of a pit and rest the toothpicks on the rim of the glass. Add water until it just touches the bottom of the pit. Kids can watch the roots and sprout emerge. Cool! It can take a month or two for roots to appear. If using the water sprouting method, replant the pit in potting soil once roots and a sprout emerge.
Mangoes are a little more difficult. Soak the hard seed for a week in warm water, replacing the water every day. Then plant it in potting soil like an avocado and settle down for a wait; it can take up to four months for a sprout to emerge.
New Plants from Tubers
Sweet potatoes and ginger --tuberous roots and rhizomes, respectively -- are plant parts that that are easy to grow into new plants. Prop a sweet potato over a water-filled glass by poking three toothpicks in a circle into the middle of the tuber and resting the toothpicks on the rim of the glass so that the narrower, pointed half of the tuber is submerged in the water. Place the glass in a sunny window. Soon roots will begin to sprout from the portion in the water, and usually within a few weeks, stems and leaves will begin to grow from the top of the tuber. To keep your sweet potato as a houseplant, carefully transplant it into a container of potting soil once a good root system has developed.
Ginger is particularly fun to grow because both the cut ends and the glossy new leaves (when crushed) emit a strong gingery aroma. Suspend a chunk of ginger with toothpicks over a glass of water or place it in a container of moistened potting soil. If using the water method, transfer the new plant to a container of potting soil once roots appear.
Off With Their (Carrot) Heads!
You can force many root crops (beets, parsnips, and carrots, for instance) to sprout new top growth by beheading them. Kids love the chopping part. Slice off the head end along with one to two inches of the root and place it in a saucer filled with pebbles for support and water. In a week or so new greens should appear from the top. Then snug the root into a container filled with potting soil.
This beheading technique also works well with pineapples. Cut off the top inch of the fruit and scoop out most of the yellow flesh inside the crown, leaving the core. Let the top dry for a day or two, then place it in a tray filled with pebbles for support and water. Roots will appear and new shoots will sprout from the top in about two weeks, and soon you'll have a fantastic tropical plant. To continue growing the new pineapple, transplant it into a pot, covering the crown and roots with soil.
For a kitchen scrap plant that's both pungent and edible, try garlic or onions. Plant old cloves of garlic or bulbs of onions just below the surface in containers filled with moistened potting soil. Within a few weeks you'll see sprouts. Unlike the other kitchen scrap plants described above, you can eat these greens in salads and stir-fries.
Place in a sunny window and watch your gardens grow!
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