Expert Gardening Tips to Boost Nanking Cherry and Rhubarb Health

Gardening enthusiasts often face challenges in helping their plants thrive, as evidenced by two recent inquiries submitted to gardening expert Gerald Filipkiger in the Edmonton Journal. These questions highlight common issues among fruit-bearing and vegetable plants, particularly the Nanking Cherry shrub and rhubarb.

Nanking Cherry Shrub: Reasons for Lack of Blooming

One reader shared concerns about their six to seven-year-old Nanking Cherry shrub, which stands approximately two meters tall and appears healthy but has yet to bloom or produce fruit. There are several potential reasons for this lack of flowering.

Primarily, an excess of nitrogen may inhibit blooming. If the shrub is located near a lawn, it could be receiving nitrogen from fertilizer applications, which might encourage leaf growth at the expense of flowers. To address this, the reader is advised to refrain from fertilizing the area directly under the tree up to its dripline. Alternatively, creating a “no fertilizer zone” by removing a circular section of lawn around the base of the tree could help. This adjustment is crucial because while the shrub shows good health, excessive nitrogen can lead to robust foliage but few or no blooms.

Another factor to consider is soil drainage. Poorly drained soil can lead to water pooling around the roots, which may hinder flowering. The shrub thrives in full sunlight, so if it is situated in partial shade, this could also be a contributing factor to its lack of blooms. Ensuring optimal sunlight and drainage will be essential for the Nanking Cherry to flourish.

Rhubarb Issues: Identifying and Addressing Leaf Spot Disease

Another reader expressed frustration with their four-year-old rhubarb plant, which has developed red and brown spots on its leaves, leading to wilting and eventual drying. Despite the plant being in good loamy soil with ample sunlight and proper drainage, the symptoms suggest a more serious underlying issue.

The conditions described align with Ramularia leaf spot, a common fungal disease affecting rhubarb. This fungus, known scientifically as Ramularia rhei, thrives in wet conditions and can significantly impact plant health.

To manage this situation effectively, the reader should take immediate action by removing and destroying any infected leaves and stalks to prevent further spread. It is critical not to compost these materials, as this may only exacerbate the issue. Additionally, ensuring adequate air circulation around the plants by proper spacing and pruning overcrowded foliage can help mitigate the disease’s impact.

If the rhubarb is currently situated in a shady, damp area, relocating it to a sunnier, well-drained location may prevent further outbreaks. While fungicides are an option, they should be used with caution on edible plants, as it is generally advisable to avoid applying chemicals to the stalks consumed.

These inquiries serve as a reminder of the nuances involved in gardening. Gerald Filipkiger invites readers to follow his column, Growing Things Outdoors, for more practical gardening advice. Questions can also be directed to him via email or through his book, Just Ask Jerry.

In gardening, understanding the specific needs of each plant is vital. With the right adjustments and care, both the Nanking Cherry and rhubarb can thrive and contribute to a flourishing garden.