AMES, Iowa — Amaryllis and narcissus are two popular flowering bulbs grown indoors during the winter months. Horticulturists with Iowa State University Extension and Outreach share information to bring blooms to Iowans' homes during January and February. To have additional plant questions answered, contact the ISU Hortline at 515-294-3108 or email firstname.lastname@example.org.
When planting an amaryllis bulb, select a pot that is approximately 1 to 2 inches wider than the diameter of the bulb. The container may be clay, ceramic or plastic, but should have drainage holes in the bottom. Plant the bulb in a well-drained potting mix. Place a small amount of potting mix in the bottom of the pot. Center the bulb in the middle of the pot. Then add additional potting mix, firming it around the roots and bulb. When finished potting, the upper one-half of the bulb should remain above the soil surface. Also, leave about 1 inch between the soil surface and the pot’s rim. Then water well and place in a warm (70 to 75 F) location.
After the initial watering, allow the potting mix to dry somewhat before watering again. Keep the mix moist, but not wet. When growth appears, move the plant to a sunny window and apply a dilute fertilizer solution every two to four weeks. During flower stalk elongation, turn the pot daily to keep the flower stalk growing straight. Flower stalks that lean badly will need to be staked.
Flowering occurs about six to eight weeks after potting. When the amaryllis begins to bloom, move the plant to a slightly cooler (65 to 70 F) location that doesn’t receive direct sun to prolong the life of the flowers.
Amaryllis are available in a wide range of colors. Flower colors include red, pink, orange, salmon, white and bicolors. Single-flowering, double-flowering and miniature amaryllis varieties are available.
Excellent single-blooming varieties include ‘Apple Blossom’ (white with pink feathering), ‘Christmas Gift’ (white with a green throat), ‘Minerva’ (red with white star), ‘Picotee’ (white with red-rimmed petals), ‘Orange Sovereign’ (orange) and ‘Red Lion’ (crimson red).
Double-flowering varieties include ‘Aphrodite’ (white with pinkish red feathering), ‘Blossom Peacock’ (rose-red with white throat and midrib), ‘Dancing Queen’ (red and white striped) and ‘White Nymph’ (white).
Miniature varieties are only slightly shorter than their single- and double-flowering counterparts. However, their flowers are about half the width of the large flowering types. Excellent miniature varieties include ‘Baby Star’ (crimson red with white center star), ‘Fairytale’ (white with raspberry red stripes), ‘Green Goddess’ (white with green center) and ‘Neon’ (fuchsia pink with white throat).
Paperwhite narcissus are easy to force indoors. The bulbs can be forced in clear, shallow bowls (no drainage holes) or pots.
When forcing paperwhite narcissus in bowls, partially fill the container with washed gravel or stones. Place the bulbs on the gravel or stones. Then place additional gravel or stones around the bulbs, leaving the tips (noses) of the bulbs exposed. Add water to the bowl until it touches the bottom of the bulbs. Maintain the water at this level throughout the forcing period.
When forcing paperwhites in pots, partially fill the container with potting soil. Place the bulbs on the soil surface. Then add additional potting soil. When potted, the tips of the bulbs should stick above the potting soil. The level of the soil mix should be ½ to 1 inch below the rim of the container. After potting, water each container thoroughly. Keep the potting soil moist throughout the forcing period.
Place the planted bulbs in a cool (45 to 50 F), dark location for two to three weeks to encourage root growth. When the shoots reach a height of 3 inches, move the plants to a sunny area with a temperature of 60 to 70 F. To prolong their bloom period, move the paperwhite narcissus from direct sunlight when the plants begin to flower. Paperwhite narcissus bulbs should be discarded after flowering. Paperwhites can’t be forced again and are not hardy outdoors.
Paperwhite narcissus varieties include ‘Bethlehem’ (creamy white petals, yellow cup, mild musky fragrance), ‘Chinese Sacred Lily’ (white petals, yellow cup, citrus-like fragrance), ‘Galilee’ (pure white flowers, moderate musky fragrance), ‘Inbal’ (white flowers, mild pleasant fragrance), ‘Grand Soleil d’Or’ (yellow petals, orange cup, sweet fruity fragrance) and ‘Ziva’ (pure white flowers, strong musky fragrance).