Plant glads after the threat of frost has passed in the spring. They respond best to moderately rich, well-drained soil. Add peat moss to the soil to aid drainage. After digging the soil to a depth of about 1’, add 5-10-5 fertilizer. Space bulbs 6” apart and at a depth equal to 2 times their diameter. If the soil is damp at planting time, water sparingly until top growth begins to show. Increase watering during the warmest weather. Even though glads need plenty of water when blooms are developing, they cannot tolerate poor drainage. Use caution when watering in heavy soil.
Bulbs will flower about 8-10 weeks after planting. Since most varieties are quite tall, it is recommended that you stake the bulbs at planting time. Glads flower from the bottom up. Cut the blooms for indoor use when the lowest blooms appear. Always leave at least 3 leaves with the plant when you cut the flower so the remaining leaves can manufacture food for the bulb. Cut down faded flower stalks. Continue to maintain the leaves after flowering is done for the year. About 6 weeks after flowering has ceased, the leaves will turn yellow. This is the time to lift the bulbs for winter storage. Gently raise the bulb, shake off the soil, dry the bulbs for several days, cut off the leaves to 2”, and dust the bulbs with an insecticide/fungicide powder. Place the bulbs in mesh or paper bags filled with dry peat moss or vermiculite. Store in a dry, 40 degree location for the winter.
Thrips are the most common insect pest. They cause streaking and mottling of the buds and flowers and russet-colored scars on the bulbs. Spray with Mal-A-Cide, Orthenex, Isotox, or Eight when the flower stalks first appear and at 7-10 day intervals thereafter. Snails and slugs can be controlled with Slug Magic. Scab, bacterial blight, yellows, and dry rot are diseases that are best controlled by purchasing healthy bulbs.
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