Tomatoes are a popular vegetable among home gardeners because they are relatively easy to grow. Gardeners who plant tomatoes can benefit immensely from harvesting and planting seeds from tomatoes they grew themselves. When you recycle tomato seeds year after year, the plants will learn to adapt to your particular soil, thereby resulting in the best possible tomatoes. Tomato seeds can easily be harvested from home without special tools.
Cut the tomato in half with a sharp knife. Scoop out the seeds with a spoon and dump them in a glass jar. Do not worry about separating the seeds from the chunks of tomato at this point.
Fill the jar 1/2 full with water. Put a lid on the jar and let it sit for two days. During this time, the good seeds will sink to the bottom of the jar while the bad seeds and tomato pulp will rise to the top.
Pour out the bad seeds and tomato pulp. Be careful not to pour out the good seeds. Fill the jar with water and pour out any leftover bad seeds or pulp. Repeat this until you are left with nothing but clear water and good seeds.
Line the inside of a colander with a coffee filter. Pour the water and good tomato seeds through the colander. The filter will let water through, but will keep the seeds.
Place the seeds in a glass dish. Put the dish outside, away from direct sunlight, until the seeds dry. The drying process generally takes four to eight days.
Store the dried seeds in a paper envelope. They are best when used within a year.