Continue to care for indoor flowering gift plants.
Azaleas require even moisture and bright light. Deadhead to keep plants blooming for four to six weeks. Azaleas can go outside to a partly shaded location after May 15, but must come back in before fall frost.
Primrose plants can be discarded after flowering or planted directly in shaded, well-drained garden area. They will go dormant during summer months and require heavy mulch to protect from summer heat and winter cold. Indoor-blooming tulip, daffodil, hyacinth, or crocus plants can be planted outside and treated like outdoor bulbs after they have flowered but there is no guarantee they will flower the following year.
Get a head start on summer-blooming bulbs and tubers by starting them indoors in moist, soilless mix. Plant Caladium (caladium), Colocassia (elephant ears), Begonia x tuberhybrida (tuberous begonia), Crocosmia (montbretia), Agapanthus (Lily of the Nile), Canna x generalis (garden canna), Polianthes (tuberose), Acidanthera (peacock orchid). Keep warm until new growth appears. Move pots into a sunny window or under grow lights if necessary. Move these pots outside when all danger of frost has passed, after gradually introducing plants to warm weather conditions.
Repot houseplants, including orchids, after they have flowered and if they have become rootbound. Increase pot size by one inch. Change the potting soil/fir bark but do not change the level at which the plant was situated in the pot.
Fertilize houseplants as they begin new growth. Try low dosages of organic fertilizers or a very dilute, balanced granular fertilizer rather than stronger formulas. Telltale white salt markings on terra cotta pots indicate overuse of fertilizer. Flush out soil of overfertilized plants with plain water.
Propagate houseplants. Softwood cuttings, leaf cuttings, air-layering, cane cuttings, or division may all be done this spring.
Start seeds of warm-season annuals and vegetables in a moist, soilless seed mix. These seeds are started six to eight weeks before the spring frost date of May 15. Transplant tiny seedlings into a "growing on" mix in slightly larger containers when they have two sets of true leaves. Gradually introduce small plants to outdoor conditions. They can be planted in containers or garden beds after May 15.