There are a number of different types of Oriental lily bulbs you can choose to plant in your garden. Rio Negro, Red Empire, Stargazer and Joyful are just a few that should be planted in the spring for a summer bloom. Knowing how often to water your lily bulbs will help prevent them from getting root rot. You should also choose a location that has well-drained soil, yet stays moist.
Your planting site can often dictate how often you need to water your Oriental lily bulbs. Bulbs need well-draining soil in order to reduce their risk of root rot or other fungal diseases. Clay soil is oftentimes waterlogged and too saturated with moisture for lilies to thrive. If you have clay soil in your yard, you should add soil amendments and reduce the amount of watering to your bulbs. You can also raise the flower bed if you area is susceptible to flooding. Sandy soil can drain too well and leave the soil dry. Make sure that you water your bulbs more frequently when you have sandy soil or make soil amendments like adding sphagnum moss to your soil. Loamy soil is ideal for most plants, because of its high organic nutrient content and draining capabilities. To find out what type of soil you have in your yard, fill a jar with two-thirds of dirt and one-third water. Shake and wait 24 hours. The sand will settle at the bottom, loam in the middle and clay at the top.
When to Water Oriental Bulbs
Start watering Oriental bulbs after planting. Dig a hole based on their type and size. Lily bulbs should be generally planted 4 to 8 inches in the ground depending on their size. Cover with soil and water thoroughly. Watering immediately after planting will aid in promoting root growth. Make sure that you plant your bulbs slightly deeper in sandy soil than you would clay soil. Water your lily bulbs once a week. You can help the water get to the bulb by watering in a slow stream, rather than spraying over the surface of the bed. Continue the watering schedule until after the Oriental lily flowers. Allow it to dry out and become dormant.
Avoiding Fungal Diseases
Botrytis blight is a common fungal disease that can occur after too much watering, watering at night, planting too many bulbs in one area, flooding and planting in areas that do not receive at least six hours of sun. You can help prevent fungal diseases by making sure your bulbs only get watered once in the week, have proper air circulation by spacing them out when planting, watering in the morning and at the base of the plant and planting in a sunny location. Inspect your lily plants for reddish brown leaves that indicate fungal diseases. Apply fungicide or prune off diseased areas with bypass shears.