How to Grow Nasturtium in Arizona

Nasturtiums are vibrant, edible flowering plants that add a splash of color and flavor to gardens across the world. Their bright orange, yellow, and red flowers attract bees and other pollinators, making them a wonderful choice for gardeners looking to create a welcoming environment. Growing nasturtium in Arizona can be particularly rewarding due to the state’s warm climate. This article will provide you with essential tips on how to successfully grow nasturtium in Arizona.

Understanding Nasturtiums

Nasturtiums (Tropaeolum majus) belong to the family Tropaeolaceae and are native to South America. They can be categorized into two main types: trailing (or vining) and bush varieties. Both types are easy to grow and can thrive in various conditions, making them suitable for home gardeners and commercial growers alike.

Characteristics of Nasturtiums

• Edibility: Not only are nasturtiums beautiful, but they are also edible. The leaves, flowers, and seeds can be used in salads, sandwiches, and as garnishes.
• Growth Habit: Trailing varieties can grow up to 10 feet long, while bush varieties typically reach 12 to 18 inches in height.
• Soil Preferences: Nasturtiums prefer well-draining soil that is slightly poor in nutrients, which encourages better flower production.
• Light Requirements: These plants thrive in full sun but can tolerate partial shade.

Choosing the Right Variety for Arizona

When selecting nasturtium varieties for your Arizona garden, consider both climate and space:

1. Trailing Varieties: ‘Cressida’, ‘Alaska’, or ‘Jewel Mix’ are great choices if you have trellising or hanging baskets.
2. Bush Varieties: ‘Tom Thumb’ or ‘Whirlybird’ are compact options ideal for small gardens or container planting.

Preparing Your Garden Bed

Soil Preparation

Nasturtiums thrive best in poor soil conditions as overly rich soil often results in lush foliage with fewer blooms. Here’s how to prepare your garden bed:

• Test pH Levels: Aim for a slightly acidic to neutral pH (6.0 – 7.0).
• Amend the Soil: If your soil is too rich, amend it with sand or perlite to improve drainage and reduce nutrient levels.
• Till the Soil: Break up the soil to a depth of about 12 inches. This helps aerate it and allows roots to penetrate easily.

Location

Select a location with at least 6 hours of sunlight daily. While nasturtiums can tolerate some shade, they won’t bloom as profusely under low light conditions.

Planting Nasturtiums

When to Plant

In Arizona, the best time to plant nasturtiums is during the spring after the last frost date or in the fall when temperatures begin to cool down. Depending on your specific location within Arizona (e.g., Phoenix, Flagstaff), these timings may vary slightly.

How to Plant

1. Seed Preparation: Soak nasturtium seeds in water for about 24 hours before planting. This speeds up germination.
2. Planting Depth: Sow seeds about 1 inch deep into the prepared soil.
3. Spacing: Space seeds about 10-12 inches apart for bush varieties; trailing types need more room depending on how much space they require for growth.
4. Watering: Water lightly after planting to ensure seed-to-soil contact but avoid overwatering.

Watering Nasturtiums

Arizona’s arid climate requires careful attention to watering:

• Frequency: Water frequently during hot spells but allow the top inch of soil to dry out between waterings.
• Method: Use a soaker hose or drip irrigation system to deliver consistent moisture directly at the roots while minimizing leaf wetness, which can lead to fungal diseases.

Fertilization Practices

As previously mentioned, nasturtiums prefer poorer soils:

• Organic Fertilizers: If needed, use a low-nitrogen organic fertilizer sparingly upon planting.
• Over-Fertilizing Warning: Avoid using high-nitrogen fertilizers as they promote foliage growth at the expense of flowers.

Pest Management

While nasturtiums are generally hardy plants, they can attract pests such as aphids and spider mites:

• Natural Predators: Encourage beneficial insects like ladybugs and lacewings by planting nasturtiums near vegetables such as tomatoes and cabbage.
• Manual Removal: For minor infestations, wash pests off with a strong stream of water or hand-pick them off the leaves.
• Companion Planting: Nasturtiums can act as a trap crop for aphids, helping protect other plants.

Harvesting & Using Nasturtium

Harvesting Flowers and Leaves

You can start harvesting flowers when they bloom fully:

• Pick flowers throughout the growing season; they are best used fresh.
• Leaves can also be harvested and used similarly to peppery greens in salads.

Storing Seeds

If you let some flowers go to seed:

1. Allow pods to mature on the plant until they turn brown.
2. Collect seeds and store them in a cool, dry place for next season’s planting.

Seasonal Considerations

Summer Heat

Arizona summers can be brutal for many plants:

• Provide afternoon shade using row covers or shade cloth if temperatures exceed 90°F regularly.
• Mulching around the base retains moisture while keeping roots cool.

Winter Care

Nasturtiums are sensitive to frost:

• In colder months, consider bringing pots inside or covering garden beds with frost cloth if frost is forecasted.

Conclusion

Growing nasturtiums in Arizona is not only easy but also rewarding! With their striking colors and versatility in both culinary uses and beneficial properties within gardens, these plants deserve a spot in your landscape. By following these guidelines—choosing appropriate varieties, preparing your garden bed appropriately, monitoring watering needs, managing pests naturally, and understanding climate considerations—you’ll ensure that your nasturtium thrives beautifully throughout the growing season.

By incorporating nasturtiums into your garden space this season, you’ll enjoy vibrant colors while benefiting from their delicious flavors—so get gardening!