Nasturtiums are beloved annuals known for their vibrant, often fiery colors and distinctive round leaves. They are easy to grow and possess a natural trailing habit, making them ideal for cascading over the edges of hanging baskets. Their flowers and leaves are also edible, adding a unique culinary dimension to their bright aesthetic appeal. Selecting the right companion plants that share the nasturtium’s specific needs is necessary to create a dynamic and appealing display.
Understanding Nasturtium Needs in Containers
Nasturtiums (genus Tropaeolum) thrive best when exposed to six or more hours of direct sunlight daily, a condition easily met in most hanging basket locations. While they can tolerate some afternoon shade in the hottest climates, consistent full sun encourages the most prolific bloom production. This sun requirement narrows the field of suitable companion plants to those that are also highly sun-tolerant.
The most distinctive cultural requirement for nasturtiums is their preference for poor or average soil fertility. Unlike many common basket plants that demand rich, heavily fertilized potting mixes, nasturtiums planted in soil high in nitrogen prioritize leafy growth over flower development. This tendency results in a lush but bloom-scarce plant, defeating the purpose of a colorful display.
For a hanging basket, the potting mix should be a standard, well-draining container mix, with minimal or no added slow-release fertilizer. Although nasturtiums tolerate poor soil, consistent watering is necessary because the small soil volume dries out quickly. Excellent drainage is necessary to prevent root rot, ensuring water never pools at the bottom of the container.
Specific Companion Plant Recommendations
The need for low soil fertility dictates that ideal companions should perform well without heavy fertilization. Creeping Jenny (Lysimachia nummularia) is an excellent trailing companion because it tolerates various soil conditions and provides bright, contrasting lime-green foliage. It creates a vigorous, spilling effect that complements the nasturtium’s looser trailing habit.
Dwarf Marigolds (Tagetes species) are a suitable filler element that adds height and structure, sharing the nasturtium’s preference for full sun and average soil. Their upright, mounding growth provides a sturdy anchor in the center of the basket, contrasting the flowing lines of the nasturtiums. Their colors, often in shades of yellow, orange, and red, harmonize naturally with the typical nasturtium palette.
Hardy herbs also make wonderful companions, as many varieties naturally prefer less-rich soil environments. Low-growing culinary herbs such as Thyme (Thymus vulgaris) and Oregano (Origanum vulgare) provide dense, textural foliage that helps fill the basket’s gaps. These herbs are highly drought-tolerant once established, aligning well with the drier conditions nasturtiums tolerate.
The silvery-white foliage of Dusty Miller (Senecio cineraria) adds textural contrast and highlights the nasturtium flowers. Dusty Miller thrives in full sun and low-fertility conditions, making it a perfect cultural fit. Its muted color acts as a visual break, preventing the basket from becoming overwhelmed by the intense yellows and oranges of the nasturtium blossoms.
A delicate trailing option is Lobelia (Lobelia erinus), which works well if placed near the soil surface to catch moisture. While Lobelia prefers slightly more consistent water than nasturtiums, selecting heat-tolerant varieties allows them to coexist successfully in the same sunny exposure. Their delicate blue or purple flowers provide a cool-toned contrast to the warmer nasturtium colors.
Achieving Visual Balance in the Basket
Effective arrangement of plants in a hanging basket utilizes the design concept of “Thriller, Filler, and Spiller.” In a nasturtium basket, the nasturtium frequently serves as the primary spiller, cascading over the edges. Filler plants, such as Marigolds or herbs, occupy the middle ground, providing volume and texture.
The center of the basket is the best location for taller, more upright plants, which act as the thriller element, drawing the eye upward. When planting, ensure adequate spacing, as nasturtiums and their companions require room to mature without stifling air circulation. Overcrowding leads to poor performance and increased susceptibility to fungal diseases.
When preparing the basket, use a standard soilless potting mix and avoid adding high-nitrogen fertilizers. Nasturtiums are sensitive to soil enrichment; a sudden influx of nutrients encourages foliage growth at the expense of flower bud formation. This ensures the plants remain focused on producing a colorful display.
Maintenance throughout the season focuses on encouraging continuous bloom and preventing companions from dominating the basket. Deadheading spent nasturtium flowers signals the plant to produce new blooms rather than setting seed. Companion plants like Creeping Jenny or Sweet Potato Vine may require periodic pruning to prevent them from completely engulfing the nasturtiums.
Regular pruning helps maintain the desired shape and density of the basket, ensuring all plants receive adequate light and air. This proactive management allows the nasturtiums to continue their bright, low-maintenance performance throughout the growing season.