The gladiolus is one of the official August birthday flowers. It is widely used in large floral arrangements in baskets and vases at weddings, funerals and events. The beautiful stalks of ruffled trumpet-shaped blossoms create an impressive garden display when planted in rows of multiple colors. They also add an element of elegance when planted in batches in an established flowerbed. The ease of planting and care of gladiolus allows the novice a chance to grow the majestic blossoms year after year.
Add fertilizer to the soil when planting gladiolus corms to ensure that the plant has the best start possible. Mix 2 lb. of 8-8-8 fertilizer per 100 square feet into the soil at a depth of 2 inches below the soil level where the bulbs will be planted. Mature corms are planted at 6 inches deep and 6 inches apart.
Stake the gladiolus plants to protect against possible wind damage once they begin to grow. Tie string to stakes that are at least 12 inches high. Insert the stakes into the garden soil in front and in back of the row of glad stalks.
Mulch the gladiolus plant bed with a 2- to 4-inch layer of straw as recommended by "The Old Farmer’s Almanac." Mulch cuts down on weeds and allows the soil to retain moisture.
Spray or dust Sevin or carbaryl on the plants if thrips are present after they have grown to a height of 6 inches. Thrips will cause the blossoms to be streaked and misshapen. A non-chemical treatment can kill thrips in the corms before they are planted in the spring. Soak the corms in 160 degree Fahrenheit water for two minutes to kill thrips that overwinter inside of them.
Water the plants daily to keep the soil moist if the area receives less than 1 inch of rain per week.
Remove wilted and dying blossoms to encourage plant growth. After the stalk has finished blossoming, cut it away from the plant with a sharp knife. Stalks can be cut for bouquets when the first two or three florets start to blossom out.