Nasturtiums are a delightful addition to any garden, renowned for their vibrant flowers and edible leaves. Originating from South America, these hardy annuals thrive in various climates, including the temperate zones of Michigan. Growing nasturtiums can be an easy and rewarding experience, and this article will guide you through the process, covering everything from planting to care and pest management.
Before diving into the specifics of cultivation, it’s essential to understand what nasturtiums are. These plants belong to the Tropaeolum genus and come in many varieties, each offering unique characteristics. Nasturtiums are often categorized into two types:
The two main species you might encounter in Michigan are Tropaeolum majus (common nasturtium) and Tropaeolum minus. Both types produce bright flowers that can be red, yellow, or orange and have a peppery flavor similar to arugula.
Nasturtiums thrive in full sun but can tolerate partial shade. In Michigan, where sunlight varies throughout the year, aim for a location that receives at least 6 hours of direct sunlight daily. Morning sun is particularly beneficial as it helps dry off dew, preventing fungal diseases.
Nasturtiums prefer well-drained soil that is slightly acidic to neutral (pH around 6.0–7.0). They are not overly demanding about soil fertility, often thriving in poorer soils where other plants may struggle. Heavy clay or overly rich soils can lead to lush foliage with fewer blooms, so consider mixing sand or organic matter into your soil if necessary.
Michigan spans several USDA hardiness zones (3-6). Nasturtiums generally flourish best in zones 4-10. Fortunately, since they are annuals in colder climates like Michigan, they can be grown every year without concern for perennial care.
Due to Michigan’s variable climate, timing is crucial when planting nasturtiums. The best time to sow seeds outdoors is after the last frost date, which typically falls between late April and early June depending on your specific region within Michigan. If you’re eager for an earlier start, consider starting seeds indoors about 4-6 weeks before the last frost date.
Choose seeds based on your design preferences; trailing varieties are great for vertical spaces while bush varieties can fill out garden beds. Reputable seed companies offer various colors and patterns, ensuring you find something that fits your aesthetic.
Direct Sowing: Plant seeds directly into the garden about 1 inch deep and 10-12 inches apart for bush varieties or 12-18 inches apart for trailing types. Water gently after sowing to settle the soil.
Transplanting: If starting seeds indoors, transplant when seedlings have at least two true leaves. Harden them off by exposing them gradually to outdoor conditions before planting them in their final location.
Nasturtiums prefer moderate watering habits. While they can tolerate drought once established, consistent moisture is important during the germination phase. An inch of water weekly should suffice—less during rainy spells and more during dry periods.
One of nasturtium’s strengths is its ability to thrive without excessive fertilization. Over-fertilizing can lead to lush green foliage at the expense of flowers. If needed, use a balanced fertilizer sparingly when planting; otherwise, allow them to flourish naturally.
Regular deadheading (removing spent blooms) encourages further flowering and keeps plants looking tidy. Additionally, thin out overcrowded plants if necessary to improve air circulation around them—this helps prevent diseases.
While nasturtiums are relatively pest-resistant due to their peppery taste—which deters many pests—they are still susceptible to certain challenges:
Aphids: Small insects that suck sap from leaves; spray with water or insecticidal soap if infestations occur.
Cabbage Worms: These caterpillars can damage leaves; handpick them off or apply Bacillus thuringiensis (Bt), a natural pest control option.
Slugs and Snails: These pests enjoy the tender leaves; consider using traps or barriers made from copper tape or diatomaceous earth around plants.
Nasturtiums are prone to fungal diseases like powdery mildew if conditions are too humid or crowded:
Once nasturtiums begin blooming—usually within 50-70 days after planting—you can start enjoying their beauty and flavor:
Edible Flowers: Use as garnishes in salads or as colorful additions to summer dishes.
Leaves: Young leaves add flavor to salads or can be blended into pesto-style sauces.
Seed Pods: Harvest when immature and green; they can be pickled as a substitute for capers.
As annuals, nasturtiums will die back with the first frost in Michigan. Before winter sets in:
Growing nasturtiums in Michigan is not only achievable but also enjoyable! With their vibrant blooms and ease of care, these plants will enhance your garden while providing culinary benefits. By following this guide—from choosing the right location through harvesting—you’ll be well on your way to cultivating these delightful annuals successfully! Whether you’re looking to attract pollinators or simply enjoy a burst of color in your landscape, nasturtiums are an excellent choice for any gardener in Michigan.