Growing Outdoor Hibiscus in Spokane

If you are looking to add a touch of tropical beauty to your garden, zone-hardy outdoor hibiscus plants are a wonderful choice, even in Spokane and its surrounding areas. While many associate hibiscus with warm, tropical climates, there are resilient varieties that can thrive in colder regions, providing vibrant blooms that bring a lush, exotic feel to your outdoor space. With blooms that can grow as large as a salad plate and lush foliage, these plants are a favorite among our customers, who have seen them flourish year after year. Throughout the following, we'll guide you through everything you need to know to grow these stunning plants successfully in our climate.

Here's how to help these gorgeous plants flourish in our climate:

Choosing the Right Variety

First, you’ll want to select hardy hibiscus varieties that can withstand the cold winters. Currently, in stock we have the species Hibiscus Moscheutos (also known as rose mallow, swamp hibiscus, crimson eyed rose mallow, or eastern rose mallow). This shrub-like perennial produces multiple stems from a single plant. These varieties are known for their resilience and can handle temperatures as low as low as -10 to -20°F.

Planting Location

Hibiscus plants thrive in full sun to partial shade. Aim for a location where they will receive at least six hours of sunlight each day. Well-draining soil is crucial, as wet, soggy soil can lead to root rot. If your soil is heavy clay, consider amending it with compost or planting hibiscus in raised beds to improve drainage.

Soil Preparation

Before planting, prepare the soil by mixing in organic matter such as compost or aged manure. Hibiscus plants prefer slightly acidic soil. A soil test can help you determine the pH level and whether any adjustments are needed.

Planting Tips

When planting hibiscus, dig a hole that is twice as wide as the root ball and just as deep. Gently place the plant in the hole, making sure it is level with the surrounding soil. Backfill with soil and water thoroughly to eliminate air pockets. Mulching around the base of the plant helps retain moisture and regulate soil temperature.

Watering and Fertilizing

Keeping the soil consistently moist but not water logged. Hibiscus plants have relatively high water needs, especially during the hot summer months. Watering your plant well at the base, will encourage deep root growth.

Fertilize hibiscus plants in early spring with a balanced, slow-release fertilizer. A formula with equal parts nitrogen, phosphorus, and potassium works well. If you feel it’s needed, you can apply a light feeding in mid-summer.

Winter Care

Winterizing your hibiscus is crucial for its survival. In late fall, after the first frost, cut back the stems (with sanitized clippers -we recommend carefully wiping the blades with 70% isopropyl alcohol) to about six inches above the ground. Apply a thick layer of mulch (straw, leaves, or wood chips) around the base of the plant to insulate the roots and protect them from freezing temperatures.

In severe winter conditions, consider wrapping the base of the plant with burlap or using a protective plant cover to offer additional insulation.

Pests and Diseases

Hibiscus plants are relatively low-maintenance but can be susceptible to pests like aphids, spider mites, and whiteflies. You’ll want to inspect your plants regularly and use insecticidal soap or neem oil to manage infestations. To help prevent fungal diseases, ensure your plant has good air circulation and water your hibiscus from the base of the plant, not overhead.

Enjoying Your Hibiscus

With proper care, hardy outdoor hibiscus can offer a spectacular display of large, colorful flowers throughout the summer and into early fall. The vibrant blooms can range from bright reds and pinks to soft whites and yellows, making them a stunning addition to any garden.

By following these tips, you'll be well on your way to enjoying a garden filled with the striking beauty of hardy outdoor hibiscus. With their eye-catching blooms and ability to thrive in cooler climates, these plants will surely bring joy year after year. Whether you're a seasoned gardener or new to hibiscus care, planting and maintaining these resilient varieties will reward you with an impressive display of color and elegance throughout the warmer months.