Nasturtium Companion Plants

Nasturtiums are more than just pretty edible flowers; they can be strategic garden allies when paired with the right neighbors. Understanding nasturtium companion plants is the first step to a healthier, more productive garden. These vibrant blooms work hard to protect your vegetables and attract beneficial insects.

This guide will show you how to use nasturtiums effectively. You will learn which plants thrive next to them and which ones to keep apart. We will cover the science and the simple steps to get it right.

Companion planting is the practice of placing plants together for mutual benefit. Nasturtiums are one of the most versatile companions you can grow. They offer a range of protective and attractive qualities that make them a garden powerhouse.

The key benefits of nasturtiums include pest deterrence, attracting pollinators, and acting as a trap crop. Their peppery scent and chemicals in their leaves repel many common pests. Meanwhile, their bright flowers bring in bees and other helpful bugs.

The Science Behind Companion Planting With Nasturtiums

Nasturtiums are effective due to their unique biochemistry. They produce glucosinolates, compounds that create their signature peppery flavor. Many harmful insects find these compounds irritating and will avoid them.

They also act as a sacrificial plant, or “trap crop.” Pests like aphids and cabbage moths are drawn to nasturtiums more than to your prized vegetables. This draws pests away, concentrating them on a plant you don’t mind sacrificing.

Best Vegetable Companions For Nasturtiums

Many vegetables see significant benefits from having nasturtiums nearby. The pairing can lead to fewer pests and better overall growth.

Cucumbers, Melons, and Squash

Nasturtiums are excellent companions for cucurbits. They help repel cucumber beetles and squash bugs. The sprawling habit of nasturtiums can also provide light ground cover, helping to retain soil moisture for these thirsty plants.

Plant nasturtiums around the base of trellised cucumbers.
Allow them to sprawl between hills of squash and melons.
Their flowers attract pollinators essential for fruit set.

Tomatoes and Peppers

While tomatoes have mixed companion reviews, nasturtiums can help. They deter whiteflies and aphids that often plague tomato and pepper plants. The ground cover can also help moderate soil temperature.

It’s best to plant nasturtiums a short distance from the tomato base. This avoids competition for water and nutrients while still providing pest protection.

Cole Crops: Broccoli, Cabbage, and Kale

This is a classic companion pairing. Nasturtiums are renowned for deterring cabbage moths and flea beetles. The moths lay their eggs on the nasturtium leaves instead of your broccoli or cabbage.

Interplant nasturtiums directly between cole crop plants.
Use them as a decorative border around your brassica bed.
Check nasturtium leaves regularly and remove pest-laden leaves if needed.

Root Vegetables: Radishes, Carrots, and Beets

Nasturtiums can help protect root vegetables from above-ground pests. Their scent may confuse pests looking for carrot flies or other root crop attackers. The flowers also attract predatory insects that keep pest populations low.

Excellent Herb And Flower Companions

Nasturtiums play well with many other beneficial plants. Combining them creates a layered defense system and a beautiful, buzzing garden space.

Aromatic Herbs

Herbs like rosemary, thyme, and oregano share similar pest-repelling goals. Planting them with nasturtiums creates a stronger aromatic barrier. This combination can confuse and repel a wider array of insects.

Pollinator Magnets

Pair nasturtiums with other pollinator favorites like borage, calendula, and lavender. This creates a reliable food source for bees and butterflies throughout the season. A robust pollinator population improves fruit yield for your entire garden.

Tall Supportive Plants

Nasturtiums can use corn or sunflowers as a natural trellis. Their vining varieties will climb these sturdy stalks, saving space. This vertical growth can help improve air circulation around the nasturtium leaves.

Plants To Avoid Planting With Nasturtiums

Not all plant partnerships are beneficial. Some combinations can hinder growth or increase disease risk. It’s important to know which plants to keep separate.

Other Trap Crops or Heavy Feeders

Avoid planting nasturtiums with other sacrificial plants, like mustard greens. You risk creating an overwhelming pest hotspot. They also should not be placed next to heavy feeders like corn, which compete for the same soil nutrients.

Certain Herbs

Some gardeners find that nasturtiums can inhibit the growth of certain herbs. This is not well proven, but many recommend keeping them away from dill and fennel. It’s often best to observe these parings in your own garden before committing to a large planting.

How To Implement Nasturtium Companion Planting

Knowing the theory is one thing; applying it is another. Follow these practical steps to integrate nasturtiums into your garden plan successfully.

Step 1: Choosing the Right Nasturtium Variety

Select a variety that suits your goal. Bushy types are great for borders and ground cover. Vining or trailing varieties are perfect for climbing or sprawling over garden edges.

For ground cover: Choose ‘Alaska’ or ‘Empress of India’.
For climbing: Choose ‘Jewel of Africa’ or ‘Climbing Nasturtium’.
For containers: Choose any compact or dwarf variety.

Step 2: Planning Your Garden Layout

Sketch your garden bed. Place your main crops first, then add nasturtiums in strategic locations. Remember to account for their spread, which can be up to three feet for trailing types.

Place them as a perimeter border to act as a first line of defense.
Interplant them in every third or fourth row among vegetables.
Use them to fill empty spaces where weeds might otherwise grow.

Step 3: Planting and Spacing Guidelines

Nasturtiums are famously easy to grow from seed. They prefer poor to average soil; too much fertilizer will produce more leaves than flowers.

Sow seeds directly in the garden after the last frost. They germinate quickly.
Plant seeds about half an inch deep and 10 to 12 inches apart.
Water well at planting, then only when the soil is dry. They are drought-tolerant.

Step 4: Ongoing Maintenance and Care

Nasturtiums require minimal care, which is part of their appeal. Regular checking is the most important task.

Deadhead spent flowers to encourage more blooms throughout the season.
If using as a trap crop, inspect leaves frequently for aphid colonies.
You can remove heavily infested leaves or spray them with a strong jet of water.
Do not over-water or over-fertilize, as this can weaken the plants.

Advanced Strategies And Considerations

Once you understand the basics, you can use nasturtiums in more specialized ways. These strategies can help you tackle specific garden challenges.

Using Nasturtiums as a Living Mulch

Their dense, low growth makes nasturtiums an effective living mulch. They shade the soil, reducing water evaporation and suppressing weed growth. This is particularly useful around tall plants like tomatoes or fruit trees.

Companion Planting for Pest-Specific Control

Target your planting based on your biggest pest problems. For aphid-prone areas, plant nasturtiums near your most valuable plants. For squash bugs, ensure nasturtiums are interplanted with your zucchini from the start.

Seed Saving for Future Seasons

Nasturtiums readily self-seed, but you can also save seeds for next year. Let a few flowers fade and form seed pods. Collect the pods once they turn from green to a pale brown and feel dry. Store the large seeds in a paper envelope in a cool, dry place.

Common Mistakes To Avoid

Even with a simple plant like nasturtiums, errors can reduce their effectiveness. Avoid these common pitfalls to ensure success.

Planting in rich soil: This causes lush foliage but few flowers, reducing their appeal to pollinators.
Overcrowding: Give them space to spread. Crowded plants are more susceptible to mildew.
Ignoring the trap crop: If you let aphids multiply unchecked on nasturtiums, they may eventually spread. Manage the pest population on the trap crop.
Forgetting to water seedlings: While established plants are drought-tolerant, young seedlings need consistent moisture to establish.

Frequently Asked Questions

Here are answers to some common questions about using nasturtiums as companion plants.

What are the best companion plants for nasturtiums?

The best companions are cucumbers, tomatoes, cabbage, broccoli, and fruit trees like apple and cherry. Herbs like mint and radishes also benefit greatly from being near nasturtiums.

Can I plant nasturtiums with beans?

This is generally not recommended. Some gardeners believe nasturtiums may inhibit the growth of pole beans and bush beans. It’s safer to plant them in separate areas of the garden.

Do nasturtiums attract good bugs?

Yes, they attract many beneficial insects. Their bright flowers are highly attractive to pollinators like bees, butterflies, and hummingbirds. They also attract predatory insects like hoverflies and ladybugs, which eat aphids.

How close should I plant nasturtiums to my vegetables?

For pest protection, plant them within 2 to 3 feet of the vegetable you want to protect. You can plant them as a border or intersperse them directly among the crops, ensuring you leave enough space for both plants to grow without competition.

Are nasturtiums good for all gardens?

Nasturtiums are versatile but can be aggressive in ideal conditions. Their trailing varieties can smother small, delicate plants. They are perfect for vegetable gardens, container gardens, and as ground cover in orchard settings, but may need management in formal or small flower beds.