This section is from the book "Commercial Gardening Vol2", by John Weathers (the Editor). Also available from Amazon: Commercial Gardening, A Practical & Scientific Treatise For Market Gardeners.
Under this name many fine strains of Impatiens Balsamina were cultivated some years ago in thousands for market, and were chiefly valued for summer bedding out. The Balsam, being an annual, is raised from seed sown in heat in February and March in pots, pans, or boxes, the seedlings being afterwards pricked out and grown on singly in pots or several in boxes. They require plenty of moisture during growth, being exceedingly fleshy in texture, and in the early part of the year a temperature up to 70° F. is necessary by day to make them develop quickly into sturdy bushy plants. They are exceedingly free in blossom, the double-flowered kinds being also very handsome.