While they are easily bought in most grocery stores, growing your own will offer you a less expensive, healthier, and more satisfying sprout experience.
There are quite a few methods for growing your own sprouts, but I have found the bag method the best by far. You can spend $15 or more on a sprouting bag, or you can make your own for a few dollars - or less if you already have some fabric on hand that you can use.
What you'll need to make the sprouting bag:
* 1/4 yard or so of natural fiber fabric (cotton or hemp are recommended)
* 1/2 yard or so of ribbon, twill tape, or twine for a drawstring
* sewing thread (to match your fabric if you like)
* sewing pins
* sewing machine
* buttonhole attachment for your sewing machine
* tailor's chalk or something else to mark fabric
* seam ripper
* tapestry needle or safety pin
* cigarette lighter or match (optional)
What you'll need to use the sprouting bag:
* seeds intended for sprouting (varieties are practically endless, see step 5 for ideas)
* clean water
* bowl large enough to rinse your finished sprouts
* container to store sprouts in
Step 1: Cut Fabric, Pin & Sew Hem
Add 1-1/4 inches to the desired height of your bag and 1/2 inch to the desired width of your bag, then multiply the width by 2. (8 inches tall + 1-1/4 inches = 9-1/4 inches; 6-1/2 inches wide + 1/2 inch x 2 = 14 inches.) This will be the size to cut your fabric. I like to make one of the long edges the selvage of the fabric. (The selvage is the edge of a woven fabric that is finished to avoid fraying.) Cut the fabric rectangle.
If you are not using the selvage edge, use the zigzag stitch on your sewing machine to "seal" the long edge of the fabric that will be the top opening of your bag. Now, with the wrong side of the fabric facing you, turn down 1-1/4 inches of the long edge (the selvage if you're using it or the zigzag finished edge if not) and pin in place. Using a straight stitch, and remembering to reverse a few stitches at each end of the seam, sew very close to your finished edge, removing pins as you come to them.
Step 2: Make the Drawstring Hole
Unfold the fabric and fold the previously seamed hem in half. At the pinned centerline, make note of where the folded top edge is now. Unfold and, using tailor's chalk or a pencil or a crayon or whatever, mark your drawstring hole and remove pin. This should be barely wider than whatever you're going to use for a drawstring.
Using your buttonhole attachment, create a buttonhole around your mark, working on the right side of the fabric. Use a seam ripper to cut the fabric in the buttonhole. Be careful not to cut the threads you just stitched, though!
If you don't have a buttonhole attachment, cut your buttonhole first and then whip-stitch around the hole to seal the edges.
Step 3: Sew the Sides & Bottom
Beginning at the top, using a straight stitch, sew along the side of the bag, leaving about 3/8 to 1/2 inch seam allowance. When you get to the bottom corner of the bag, stitch to 1/2 inch from the bottom edge, and with your needle down in the fabric, lift the presser foot of your machine and turn the fabric 90 degrees. Now stitch the bottom edge of the bag. Be sure to do a few reverse stitches at the beginning and end of this seam to prevent unraveling.
Your fabric edges might be a little uneven - that's okay. Go ahead and use your scissors to trim the edges to about 1/4 to 3/8 inches from your seam. Now run a zigzag stitch along this edge, with the edge of the fabric in the center of the stitch. This is the poor (wo)man's serger!
Step 4: Create the Drawstring Channel
With a straight stitch, working on the right side of the fabric, sew along the first hem seam you created in this project. Be sure to reverse a few stitches at the beginning and the end of your seam.
Thread your tapestry or yarn needle with the drawstring you're using, or pin a large-ish safety pin through one end of the drawstring. Insert the needle/safety pin in the buttonhole and begin to work the drawstring through the channel, gathering the fabric and sliding it along toward the "tail" of the drawstring little by little. When you reach the buttonhole again, pull the ends of the drawstring even and knot them.
If you use something that will fray, like the grosgrain ribbon I chose, you'll want to finish the ends somehow. You can heat-seal them with a quick flick through a lighter or match flame or you can turn the ends down and stitch them.
Step 5: Growing Your Sprouts
Do your research - some of the beans should be cooked after sprouting, as they can be difficult to digest without cooking. They cook far faster after sprouting, though, and are better for you. Some grains and nuts will not really form a sprout, but a nice swelling at the germ of the seed. They are still delicious and good for you.
Put your seed into the sprouting bag and place the bag in a container of cool, clean water. I use about 1 tablespoon of small seed in mine - a bit more for beans or larger seeds. Leave the closed bag in the container of water to soak. Each seed has its own soaking time, so you'll want to check, but most of the seeds I use tend to need 8-12 hours of soaking.
After soaking, swish the bag around in the bowl a bit and hang. You'll want to put a towel or sponge or something under the drip. About every 8 hours or so (you'll get the feel for this with your particular seeds and the type of fabric you use), either swish and dip your seeds in a bowl of water or rinse under running water. Re-hang.
When the sprouts are as big as you want them, remove them from the bag and put into a large bowl of cool water. Turn the bag inside out and rinse to get rid of any hulls clinging to the bag, and squeeze it as dry as possible. Swirl the sprouts in the water, breaking up the mass of sprouts and letting the hulls drift away from the sprouts. When you have as many hulls freed as possible, remove the sprouts from the bowl. You can repeat this process as many times as you like to get rid of hulls.
Return the sprouts to the bag. Go outside and swing the bag around and around in big circles - you're using centrifugal force to get as much water out of the sprouts as possible, because putting them away wet will cause them to go bad very quickly.
Put the sprouts in a clean plastic or glass container. You can put them in a windowsill or other spot that gets indirect sunlight for a couple of hours if you want to let them develop a bit of chlorophyll (turn green). I usually line the bottom of my container with a paper towel and place a piece of paper towel on top of the sprouts in the container, too. Really, you want to keep them from being too moist! Sprouts will keep for weeks in the fridge.