Choose a spot to plant your triplet lily bulb, which is also called a "corm." The ideal location is partially shaded, perhaps sheltered by a tree. Plant the corm in a slightly elevated location in the garden or yard to ensure good water drainage.
Choose the right time to plant your triplet lily. Triplet lilies should be planted in early spring, when flowers in the area are first beginning to bloom.
Using a small gardening spade, dig a small hole in the soil about 4 to 6 inches deep. If you are planting more than one corm, place them about 6 inches apart so they will have plenty of room to grow.
Cover the corms with soil and add some planting mulch to the top. The mulch will keep the corms insulated against warm and cold weather.
Water the planting area about three to four times a week. Once the flowers begin to grow, you will only need to water them about twice a week. Triplet lilies do not require a lot of watering and are well adapted to warm, dry climates. Do not overwater the corms of they could fail to bloom.
Add a small amount of slow-release fertilizer to the base of each lily once the plants begin to emerge from the ground.
Cover the plants with a sheet if cold weather is expected. Frost can damage or kill triplet lilies.