Gardeners in South Central Kansas face challenges that require careful planning for horticultural success. Understanding the local climate is the foundational step for selecting plants that will thrive in the Wichita area. Planting zones offer a standardized guide for assessing a plant’s ability to withstand winter temperatures, which primarily determines perennial survival. This guide aligns plant selection with Wichita’s specific environmental conditions.
Identifying Wichita’s Plant Hardiness Zone
The official measure for determining a plant’s ability to survive winter cold is the USDA Plant Hardiness Zone Map (PHZM). This system divides North America into zones based on the average annual minimum winter temperature. Wichita, Kansas, is currently categorized as USDA Plant Hardiness Zone 7a.
This designation means the lowest expected temperature range falls between \(0^{\circ} \text{F}\) and \(5^{\circ} \text{F}\). This classification is a recent update; the region was previously classified in Zone 6b, where temperatures could drop to \(-5^{\circ} \text{F}\). When purchasing perennial plants, shrubs, or trees, looking for a tag that lists Zone 7 or colder indicates winter survivability. The hardiness zone only addresses cold tolerance and does not account for other local environmental factors that influence plant health.
Understanding Local Growing Conditions
While the hardiness zone defines the winter minimum, successful gardening in Wichita also depends on the distinct growing season and soil characteristics. The average last spring frost occurs between April 16 and April 20, marking the start of the frost-free growing season for tender annuals and vegetables. This period extends until the first fall frost, which arrives between October 21 and October 27, yielding an average growing season of approximately 187 days.
Summers are characterized by intense heat, with the area experiencing 61 to 90 days where temperatures exceed \(86^{\circ} \text{F}\). This prolonged heat necessitates selecting species with strong heat tolerance to prevent scorching and dormancy. Kansas is also known for persistent high winds, which can rapidly desiccate foliage and break stems, requiring wind-resistant plants.
The native soil composition in South Central Kansas is varied, often presenting challenges like heavy clay, though loamy and silty soils are common. The soil pH is typically alkaline, often measuring 7.2 or higher. This high pH can affect the availability of certain micronutrients, such as iron, making soil amendments or the selection of alkaline-tolerant plants necessary.
Selecting Plants for Zone Resilience
Successful planting involves matching the plant’s stated zone hardiness to the local Zone 7a designation, then filtering that selection based on specific local environmental conditions. Choosing plants labeled for Zone 7 or lower ensures they withstand winter cold, but they must also be resilient against summer heat and high winds. Native Kansas plants are well-suited because they have adapted to the entire range of local weather extremes and soil pH.
For durable groundcover and perennials, look to drought-tolerant natives like Purple Coneflower (Echinacea), Black-Eyed Susan (Rudbeckia), and various species of Yarrow (Achillea). These choices thrive in full sun and handle drier conditions once established, which is an advantage during periods of low rainfall.
When considering shrubs, options like False Indigo (Amorpha fruticosa) and Wild Plum (Prunus americana) are known for their resilience and ability to handle the alkaline soil and windy prairie environment. Utilizing plants with built-in tolerance for the local climate simplifies maintenance and increases the likelihood of long-term success.