Stop growing vegetables on their own.
A bed of leaves gives a bee no reason to stop. Alyssum, marigold, borage and cosmos sown with the vegetables.
Zucchini, pumpkin, cucumber, melon and strawberry set more and better-shaped fruit when bees visit, and cucurbits need an insect to carry pollen from male to female flowers. A vegetable bed with no flowers gives bees little reason to stop. Sow alyssum, marigold, borage, nasturtium, zinnia and cosmos among the vegetables when you sow the vegetables, so they flower together, and never spray open flowers while bees are working.
A vegetable bed is, for most of spring, a bed of leaves. Neat rows, nothing in flower, and then in November the zucchini opens its first female flower and waits for a visitor that has no reason to be there. Lesson 3 covered the hand-pollination fix. This lesson is the one that means you rarely need it.
Why the vegetables need the flowers
Zucchini, pumpkin, cucumber and melon carry separate male and female flowers on the same plant, and pollen has to be carried from one to the other for the fruit to set. Bees do the carrying. Gardening Australia's cucurbit guide puts it plainly: this can be a problem if you do not have enough honey bees to do the pollination for you. Strawberries set more and better-shaped fruit with bee visits too.
Tomatoes, capsicum and chilli can self-pollinate, but Australia's blue banded bees buzz-pollinate them, shaking the pollen loose by vibrating their flight muscles against the flower, and in glasshouse trials they set fruit more efficiently than honey bees. Beans mostly self-pollinate; bees are a bonus there rather than a requirement.
What a flowerless bed is missing
Visitors. Australia has European honey bees and more than 1,700 named native bee species, blue banded bees, teddy bear bees and stingless bees among them, and a bed of leaves gives none of them a reason to stop. Flowers in or beside the bed can bring more pollinators to the crops and, as Gardening Australia's "Bring in the Bees" points out, the beneficial insects that are the natural predators of pests like aphids (Aphididae).
The small, open flowers do the pest work. Alyssum, and the umbels of dill, parsley and coriander left to flower, feed hoverflies, lacewings, ladybirds and tiny parasitic wasps. A single hoverfly larva can eat hundreds of aphids.
The flowers to sow, and where
Six do most of the work, and all of them go from seed.
- Alyssum: low, quick from seed, self-sows, and the hoverfly plant. Scatter it through the bed as a low edging or living mulch around leafy crops; it competes with very little.
- Marigold (Tagetes) and calendula: bees, hoverflies and other beneficial insects, and calendula petals are edible. They are different plants: calendula prefers a cool-season sowing, so in the warm capitals it goes in earlier than the marigolds.
- Borage: a bee magnet for honey bees and native bees, and it self-seeds freely, so let a few go.
- Nasturtium: bees and hoverflies, and many gardeners use it as a decoy that draws aphids away from the crops. Flowers, leaves and green seed pods are all edible.
- Zinnia and cosmos: the long summer flowers. Easy from seed, still going in the heat, and busy with bees, butterflies and other pollinators when little else is.
- Sunflowers: bees now, and a head or two left standing feeds the birds later. Tall types cast shade, so put them on the south side of the bed.
Leave some herbs to flower at the end of the season as well: coriander, dill and parsley umbels and basil spikes feed the beneficial insects for weeks.
When to sow them
Sow the flowers when you sow the vegetables, so the two flower together. That is September to November in most capitals, and after the last frost in Canberra and Hobart, which on average falls in early November and in some years runs into mid November. Alyssum and calendula can go in first; zinnia, cosmos and sunflower want the warmth that tomatoes and zucchini want.
The one rule that protects them
Most contact insecticides, organic pyrethrum included, kill bees and hoverflies on contact. Do not spray open flowers while bees are working. If a pest forces your hand, spray at dusk, on the pest and not the bloom, which is the timing the NSW Department of Primary Industries and Regional Development sets out in its guide to reducing pesticide damage to honey bees.
A note for every zone
The list can work in every capital, with the timing shifted. Perth and Adelaide gardens can get a long run from alyssum and nasturtium in spring and again in autumn; both often stall in the worst of the dry summer heat, when cosmos and zinnia carry the bed. Brisbane readers should lean on cosmos and zinnia, which usually carry through the humid months. Melbourne, Canberra and Hobart sow the tender ones, zinnia, cosmos and sunflower, after the last frost, and start with alyssum and calendula in September.
Grow it: seeds in stock
Six flowers from the range, all sown in spring.
Alyssum Rosie O'Daythe low, pink living-mulch edge that hoverflies work all season.See the seeds
Marigold (African) Crackerjacktall orange and gold heads for the back of the bed.See the seeds
Zinnia Peppermint Stickstriped summer flowers that keep going in the heat.See the seeds
Borageblue stars, bees in droves, and a plant that sows itself next year.See the seeds
Nasturtium Yeti Creamcream flowers, edible from leaf to seed pod, and the aphids' preferred address.See the seeds
Cosmos Dwarf Sensation Mixeda compact cosmos that flowers for months without staking.See the seeds
Grow the flowers and the bees do the work you would otherwise be doing with a paintbrush at seven in the morning. If your zucchini is already flowering and dropping fruit, the hand-pollination lesson gets you through this week while the alyssum comes up.
Frequently asked questions
Will flowers take water and nutrients from my vegetables?
Alyssum, nasturtium and calendula are small plants that sit at the edge of the bed and, in most gardens, compete with very little. Give the taller ones, sunflowers especially, their own spot on the south side so they do not shade the crops.
Do marigolds repel pests?
The evidence is thin. Some Tagetes species can suppress root-knot nematodes (Meloidogyne spp.), but only when grown thickly as a cover crop for a season before the vegetables; a few plants dotted through the bed will not do it. Grow marigolds for the bees and hoverflies they bring.
Are there bumblebees in Australia?
Not on the mainland. Tasmania has an introduced bumblebee; everywhere else the visitors to your borage are honey bees and native bees.
How close do the flowers need to be to the vegetables?
In the same bed or the next one. A bee working alyssum at the edge of the bed will often move across to a zucchini flower in the same bed.
