5 Useful Flowers to Deter Pests in the Vegetable Garden

Here are five really useful annual flowers which attract more pest predators into your garden to help in the fight against pests. And also use these flowers to feed your crop plants for even bigger, better harvests. Sounds good, right?!

Hardy Annual Flowers

Let’s start with tough, resilient flowers that, with any luck, will pop up time and again. They are annuals but also are all self-seeders, which means the seeds that they drop will survive to come up next spring: Sow once, enjoy for many years to come! These flowers not only attract pollinating insects like bees, but also pest predators such as hoverflies, lacewings and ladybugs or ladybirds. 

1. Calendula

Sunny calendula (also known as pot marigold) thrives in pretty much any garden soil, including poorer soils. It loves the sunshine but does okay in light shade too. What an accommodating flower! You can eat the petals – they look fabulous in salads and soups – and it’s a great companion plant because studies have shown it helps repel pests like aphids, brassica-eating caterpillars, and armyworms. 

• Calendula is best sown directly into the soil where it is to grow. The soil should be prepared in advance by just loosening it up to create a fluffy texture that’s good for sowing. Just to be sure, and to give an extra helping hand, fork in a little garden compost.
• Sow about a half inch deep. Just push them down here and there. They will be thinned out once they’re up.
• In late winter/early spring, you could also sow in plug trays at the same depth. 

2. Nasturtium

Nasturtiums are really great at luring away brassica-eating butterfly caterpillars from your vulnerable crops like kale and broccoli. Expert gardeners know nasturtium well. They’re an excellent trap crop in companion planting, drawing aphids and other garden pests away from the more valuable vegetables.

This cheery flower is a friend of; beans, broccoli, cabbage, cucumber, kale, melon, pumpkin, and radish.

Pests aren’t the only thing nasturtiums attract, however. Nasturtium is a boon for the bees. Butterflies and hummingbirds love them, too. And every part of this plant—from the leaves to the flowers to the spicy seedpods—is edible! Pop those nasturtium flowers in your mouth! 

Nasturtiums are grown as annual plants in most areas, though they may perennialize in frost-free zones. Sow in plug trays in advance. But wait to sow them outside until well past any chance of frost. Although they are frost hardy, they are a touch on the delicate side to start with.

3. Borage

Beautiful borage is stunning with its starry blue or white flowers and attracts all sorts of bees, especially those raucous bumblebees. In fact, borage is so attractive to bees that a few of its alternative names include bee’s friend and bee flower. Bees go bonkers for borage – sounds like a good headline! 

Borage is known to dissuade insect pests such as tomato hornworm and cabbage white butterflies or cabbageworms, probably because of all the frenetic bee activity around them. Borage is a good companion to tomatoes and cabbages, encouraging a good flightpath of bees back and forth between them! Borage is also meant to improve the flavor of strawberries, too.

As this is a Mediterranean native, it’s going to do best in full sunshine. Borage is great at drawing up nutrients from the soil, so you can harvest the leaves and the flowers are edible, too! Pick the flowers and drop them into drinks as a star-gazey garnish, as the crowning glory to a cake, or perhaps into salads along with other edible blooms like nasturtium. Borage flowers have a crisp, refreshing cucumber flavor – just the job for a quenching summer punch! 

Borage has chunky seeds which can be sown through early summer. Borage is an annual flower that dies at the end of the season, but… it readily self-seeds as nicely as any perennial. Once borage starts flowering it should go on and on for several weeks, but also help plants along by deadheading, or removing the old flowers – just cutting them off to encourage more – and you can also rejuvenate plants midseason by pruning them back about halfway. 

4. Poached Egg Plant

No, we’re talking about the vegetable. Poached egg plant, or Limnanthes, is loved by pollinators, while attracting the likes of aphid-hungry hoverflies. It grows in sun or part shade, and prefers a free-draining soil. And what a stunner of a plant! Can you see (from the video) how it gets its name?

• Sow outside in little clusters, then thin the seedlings to about 4 inches apart once they’re up. Like the other two, this flower readily self-seed and is hardy, so their sunshine cheer should be with you for summers to come.
• A little-known benefit of poached egg plant is that it can be dug into the ground before it sets seed to serve as a cover crop or green manure. So it’s also good for sowing in spaces that will be planted later on with autumn crops.

Frost-Tender Annual Flowers

Of course, it’s worth sowing half-hardy, or frost-tender annuals too! 

1. Alyssum

This is another one for attracting hoverflies. It’s a small, almost ground-hugging annual, which makes it a super choice for not only slotting in here and there right in among aphid-vulnerable crops such as lettuce, but also to use as edging to beds.

2. French Marigold

A well-behaved frost-tender annual that needs little introduction, French marigold has a fairly compact shape, which means it sits quite happily beneath taller plants like, in this case, tomatoes. It adds a splash of color to the productive garden but, more usefully for us veggie growers, it attracts a slew of pest predators: lacewings, hoverflies, tiny wasps, ladybugs or ladybirds – you name it! 

If you’ve had problems with root-knot nematodes in past years, consider growing marigolds and then, towards the end of the season, chop up the plants and dig them into the soil where they’ll release natural chemicals that will interfere with those nuisance nematodes.

Don’t forget to deadhead marigolds regularly to keep the flowers coming, and give them a sunny spot to help them bloom to their full potential. The flowers can also be eaten – in moderation. They have a citrusy tang that’s ideal in salads or as a garnish to desserts. Lovely stuff!

3. Zinnia

A bit taller at around 2-feet-tall, zinnia should offer a bit of height as well as cheer. Zinnias are great for butterflies, particularly monarch butterflies and painted ladies. Give zinnia a sunny spot – it’s good for both the plants and the nectar-sipping butterflies that come to visit. 

• To start early, sow each zinnia seed into its own seed flat or pot of seed-starting mix. This should give the best germination. Sow very thinly onto the surface of lightly firmed, moist seed-starting mix then covering with a very fine sprinkling of vermiculite (or you could use a little more of the same seed-starting mix). Thoroughly mist spray to moisten the sown seeds.
• All of these frost-tender annuals need a little warmth to get them going, so pop a bit of polythene over the top, secured in place by a rubber band, then pop them into a tray covered with a humidity dome for extra snugness. They’re going onto a warm windowsill, just above a gentle heat source to speed germination. Ideally, they’d be at around 75 Fahrenheit or 23 Celsius, so if you have a heated propagator, use that, as it will be more consistent and faster.
• Once the seedlings are up, transplant them into their own large plug trays to grow on. 
• Harden off seedlings over the course of a week or so (bring them outside for brief periods so they adapt to outdoors). They’ll be ready to plant out after the last frost date. 

A Perennial Superstar: Comfrey

Though this article is mainly about annual flowers, it’s worth highlighting a perennial—comfrey which is a huge favorite of bees with its gorgeous, drooping clusters of almost bell-shaped blooms. Comfrey also attracts plenty of hungry pest-munchers such as tiny parasitoid wasps, lacewings and spiders.

Comfrey is a good plant to place at the back of a border of the vegetable garden. Plant next spring, and comfrey will eventually form a really satisfying clump, for a true comfrey patch. Note that the wild variety of comfrey can self-seed and spread – a lot! – so to avoid that we recommend the variety ‘Bocking 14’, which is a sterile, garden-friendly variety that’s far-better behaved!

The real joy of comfrey, however, isn’t in the flowers – fab as they are – it’s in their leaves. Comfrey has deep roots that draw up nutrients from far down in the soil. These nutrients accumulate in their leaves in a far more bioavailable form – and we can use that to our advantage in a few different ways.

The leaves have lots of nitrogen in them, loads of potassium and a host of trace elements too, which makes them a fab, natural, slow-release fertilizer. 

• The first way to use them is to simply cut and drop the leaves around plants that will appreciate the extra boost: fruit trees, bushes and canes, for example, as well as fruiting vegetables like tomatoes and squash. You could even combine comfrey leaves with a topping of, say, grass clippings to give your hungry plants even more nutrients to guzzle! 
• Leave the wilted leaves on top of the soil as a mulch or dig them in early in the season like a cover crop or green manure to enrich the soil for a future crop. Or dry the leaves then crumble them into homemade potting mixes for a little extra nutrition.
• Add comfrey leaves to the bottom of planting holes too – for fruiting vegetables or to line the bottom of potato trenches. Their searching roots will stumble upon the comfrey leaves just as they’re beginning to break down and release their nutrients back into the soil – perfect! 
• But the absolute best way to unlock the power of comfrey is by making a quick-acting liquid fertilizer. And it’s so simple to make a “plant tea.” See on how to make an organic plant fertilizer.

See Ben demonstrate how to grow these really useful flowers in the veggie garden!

Flowering Herbs With Vegetables

Don’t forget that many common herbs are really fantastic sources of nectar and pollen for all sorts of beneficial bugs. High up on the list are basil and parsley, perfect at ground level beneath climbing beans to keep them trouble-free.

• Find living herbs from the grocery store very cheaply. These can then be split up and re-potted, to grow on a bit before planting out into their final positions a few weeks later.
• There’s one herb you don’t often see for sale though, and that’s dill. Pick up a packet of seeds and simply scatter the seeds where they are to grow once it’s warmed up. The seeds will be raked in, to ensure good contact with the soil, before the area is thoroughly watered to set them on their way. Dill flowers are almost identical to fennel, which is a taller perennial herb and an absolute beauty for many years of insect-attracting blooms. And there are, of course, many insect-friendly flowering perennial herbs you can include, such as chives, rosemary and sage.

We drop all these flowers into our garden plan for the coming growing season. We can’t wait to see how these beautifies help boost crop growth.  What vegetable garden-friendly flowers are you planting this season? Tell us in the comments below.