Some of my early, organic urban gardening attempts resulted in wilted produce, eaten alive by aphids and other pesky bugs, and I almost gave up growing one of my favorite greens altogether – lettuce. But there are fairly simple techniques any gardener can utilize to survive these woes and create a stellar organic garden – something called additive intercropping is one of those techniques.
Whether you want to grow butter lettuce for a beautiful garnish, endive or arugula for gourmet salads, or one of the many hundred other varieties besides Iceburg for both their nutrition and taste, it can be simply maddening to have a good crop of baby greens started only to be devoured by insects. The great news is that you can grow your greens without pesticide, and do it beautifully, simply by planting the right variety of flowers as companions to your lettuces.
How Flowers can Naturally Protect Your Food – The Dynamic Duo
Companion planting is nothing new to organic farmers and gardeners. It was a mainstay of crop sustainability for millennia before Big Ag ever devastated the landscape with genetically modified organisms meant to withstand copious spraying of herbicides, fungicides, and pesticides.
Read: 5 Beneficial Bugs that Could Help Your Organic Garden Grow
New research provided by the USDA’s Agricultural Research Service has shown that lettuce growers can control one of the most devastating bugs by simply planting sweet alyssum flowers (Lobularia maritime).
This unassuming, dainty looking flower blossoms in a bush, and grows in a palate of white to pink, to deeper fuscia colors.
Sweet alyssum attracts beneficial insects including hoverflies, whose larvae each chomp down as many as 150 aphids per day. This can translate into a 5 percent increase in plant yields for conventional lettuce farmers, and is none-too-shabby for the urban gardener or small farmer looking to boost yields and eliminate chemical usage also.
Using a technique called additive intercropping developed by USDA researcher Dr. Eric Brennan, lettuce farmers can plant enough sweet alyssum to control pests without taking up precious acreage meant to grow edible plants. By planting just one or two sweet alyssum pants per 50 lettuce plants, aphid damage is dramatically reduced.
Alyssum also provides nectar and pollen to beneficial bugs including bees and butterflies that have been devastated by neonicotionoids and other pesticides developed by the Big Ag model.
Prettier Gardens, Higher Yields, Fewer Pests, Less Weeds
Furthermore, research from the University of Copenhagen suggests that weed control can be conducted more sustainably by adjusting sowing patterns and crop density. This includes companion planting.
UC studies have demonstrated that modified sowing patterns and closer crop spacing results in a reduction of total weed biomass. The trick is to increase crop-weed competition and utilize the crop’s head start so that it gains a substantive competitive advantage over neighboring weeds.
For smaller farms and gardens, sweet alyssum can be used as a border for raised beds or in pots surrounding plants grown on patios or rooftops, not only reducing insect pests, but for beautifying space. You can also plant alyssum in hanging baskets and allow them to cascade over their containers, making a stunning pest-free addition to any space.
Flowers Not Chemicals
The next time you want to give up growing tender greens, try companion planting with sweet alyssum. Not only will your garden thrive, but as the wind carries the scent of honeyed-blooms to your nostrils, you’ll wonder why anyone ever considered a chemical insecticide to grow lettuce at all.
Additional Flowers for Insect Pest Control
For further flower-companion crops, you can try planting:
- Chrysanthemums – Wonderful multi-colored blossoms found at many expensive florists’ shops that also repel Japanese beetles.
- Borage – A flowering herb that is currently grown more in Europe than the US, but which more than adequately deters cabbage worms and horn worms.
- Clover – A cover crop that yields thousands of tiny pink flowers. It also pairs well with cabbage and other cruciferous vegetables to deter aphids and cabbage worm.
- Lavender – Used in every conceivable health and beauty product for its incredible, calming scent, lavender can also beautify your garden or urban farm with its purple-hued flowers. Lavender is a great pest-repellent for fleas, moths, and mosquitoes.
- French marigold – This sunny-hued flower keeps whiteflies away from tomatoes, and deters many other pests from multiple edible plants.