As spring unfolds, gardeners everywhere begin to face the inevitable rise of pests. In southeastern North Carolina, insects become more active around late April, causing potential damage to plants. However, by incorporating specific flowers into your garden, you can repel these pests naturally. Below, we discuss four effective flowers that, when planted properly, help deter insects from wreaking havoc in your garden, and we’ll also touch on one common flower that you might want to avoid.
Alliums: A Natural Shield Against Pests
One tried-and-true method of pest control is interplanting vegetables with alliums, such as onions, garlic, leeks, and shallots. These plants emit a strong scent that naturally repels many pests. However, a challenge arises when the alliums are harvested, often in June, leaving your garden unprotected during the most intense pest seasons of July and August.
Fortunately, alliums are not your only option. There are various flowers that can provide season-long pest control while also attracting beneficial pollinators.
Flower #1: The Sunflower – A Pest Magnet (For a Good Reason)
Sunflowers are one of the best flowers for attracting pests – but not in the way you might think. Rather than repelling pests, certain sunflower varieties, such as the Peridovic sunflower, serve as a distraction crop. These flowers are incredibly attractive to pests like shield bugs, leaf-footed bugs, and stink bugs. Instead of planting them within your garden, you should place them on the outskirts to lure pests away from your crops.
The secret lies in timing. Sunflowers become especially attractive to pests once they start to die back and produce seeds. Therefore, it’s beneficial to stagger sunflower plantings throughout the season, ensuring you always have sunflowers at various stages of growth. This way, you can continuously divert harmful insects from your tomatoes, peppers, and other vulnerable plants.
How to Plant Sunflowers for Maximum Effect
- Plant sunflowers outside your garden. Position them in nearby beds, allowing pests to focus on the flowers instead of your crops.
- Stagger the planting. By sowing seeds every few weeks, you’ll maintain a balance between young sunflowers attracting pollinators and older sunflowers distracting pests.
Flower #2: Borage – The Tomato Protector
Borage is another fantastic flower to plant in your garden, particularly alongside tomatoes. It’s known for repelling the tomato hornworm, one of the most destructive pests for tomato plants. Additionally, borage helps deter cabbage moths.
However, there’s a potential downside to planting borage. The plant is a prolific self-seeder, meaning it can quickly spread throughout your garden if allowed to go to seed. To prevent this, you should monitor the plant closely and remove it when it begins to droop, preventing it from spreading uncontrollably.
How to Manage Borage in Your Garden
- Interplant with tomatoes: Position borage between your tomato plants to shield them from hornworms and cabbage moths.
- Monitor closely: Pull the plants before they go to seed to avoid excessive spread.
Flower #3: Nasturtium – A Double-Edged Sword
Nasturtiums are another powerful addition to your garden, especially for those battling cucumber beetles and squash bugs. These pests can be a nightmare for anyone growing cucumbers, zucchini, melons, and other members of the cucurbit family.
When properly interplanted, nasturtiums help to confuse and repel these pests. However, there’s a catch: nasturtiums can also attract undesirable insects like aphids and cabbage moths. Therefore, if you’re growing brassicas like cabbage, kale, or broccoli, keep the nasturtiums away from these plants.
Best Practices for Nasturtium Planting
- Interplant with cucurbits: Allow the nasturtium vines to grow among your squash, zucchini, and cucumbers to repel pests.
- Separate from brassicas: Keep them away from cabbage and other susceptible crops to prevent attracting pests like aphids.
Flower #4: Pyrethrum Daisy – The Ultimate Insect Repellent
One of the most exciting pest-repelling flowers is the pyrethrum daisy (species Tanacetum cinerariifolium). This flower is known for its connection to pyrethrin, a powerful natural insecticide derived from the chrysanthemum flower. Pyrethrin is a neurotoxin to many pests and is effective against nematodes, leaf hoppers, ticks, harlequin bugs, spider mites, and cabbage moths, among others.
What’s even more exciting is that while pyrethrum daisies repel a wide range of pests, they are actually highly attractive to beneficial pollinators like bees. This makes them an excellent addition to any garden focused on both pest control and promoting pollination.
How to Grow Pyrethrum Daisies
- Ensure proper identification: The pyrethrum daisy is sometimes sold under the name “painted daisy,” but not all painted daisies have the same pest-repelling properties. Be sure to buy seeds of the correct species (Tanacetum cinerariifolium).
- Plant in well-drained soil: These flowers do well in sunny locations with well-draining soil. They can be susceptible to leaf miners and aphids when young, so monitor them closely.
How to Use Pyrethrum as an Insecticide
If you’re interested in making your own natural insecticide, you can crush the heads of dried pyrethrum daisies to extract the pyrethrin. However, the plants themselves won’t harm beneficial insects, so you can safely grow them without affecting pollinators.
Frequently Asked Questions
- Which flower is best for repelling tomato hornworms? Borage is highly effective at repelling tomato hornworms when interplanted with tomatoes.
- How can I prevent borage from spreading uncontrollably in my garden? To prevent borage from self-seeding, pull the plants before they go to seed and consider succession planting.
- Can sunflowers repel pests on their own? Sunflowers don’t repel pests directly; they act as a distraction crop, attracting pests like leaf-footed bugs away from your garden.
- Are nasturtiums safe to plant near cabbage? No, nasturtiums attract pests like cabbage moths and should not be planted near brassicas such as cabbage.
- Do pyrethrum daisies harm pollinators like bees? No, pyrethrum daisies are actually attractive to pollinators and won’t harm beneficial insects in their natural state.
- What is pyrethrin, and how is it used? Pyrethrin is a natural insecticide extracted from the chrysanthemum flower. It’s potent against many pests but is safe for plants and pollinators.
- Can I plant different types of sunflowers for pest control? It’s best to use the Peridovic sunflower variety for distraction planting, as it is highly attractive to pests like stink bugs.
