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After 2 weeks, pick out any seedlings that are growing near the edge of a cell or have grown crooked and sideways. Leave about 5 seedlings in each cell so they will not be overcrowded as they continue to grow. After the seedlings grow 6 to 8 inches (15 to 20cm), their roots will be too crowded to stay in the cell tray. Pre-moisten the potting soil in a 2 gallons (7.6L) pot and make an indentation with your finger equal to the size of one of the cells. Squeeze the bottom of the cell tray to push out the root ball of the tobacco and place it in the indent you've made. Separate the cells from the tray by cutting them individually with a pair of scissors. If the tobacco plant starts to droop or wilts to one side, use a wooden barbecue skewer to support it upright. Find a fertilizer at your local gardening store that does not contain chlorine and provides nitrogen to your plant in the form of nitrate. Since tobacco is in the same family as tomatoes and peppers, fertilizers manufactured for their use will work just as well. Follow the directions on the package to determine how much fertilizer to use. Do not apply any fertilizer after flowers begin to form. The more sunlight your plant gets, the larger it will grow. Tobacco plants need full sun throughout the day, so keep them near a large window. If the weather does not drop below freezing, you can also keep them outside during the day and return them inside at night. You can also use grow lights to provide enough light for the plant as well as additional warmth. As tobacco grows, it will require more water. Check the soil daily and keep it moist with a watering can. Don't allow the water to puddle on the surface. Excessive water will promote diseases like bed rot or mildew to form in the roots. Once a flower forms and blooms, the tobacco will stop growing for the season and reduce your total yield. To keep your plant growing, use a pair of pruning shears to cut off the flowers before they blossom.
Pluck out half the sprouts from the cell tray with tweezers. Transplant seedlings into pots when they are 6 to 8 inches (15 to 20cm) tall. Apply a fertilizer with nitrate and no chlorine. Keep tobacco in an area with 6 hours of sunlight. Water the tobacco so the soil is wet, but not drenched. Cut off flowers as they begin to form.