We found a helpful article:
Pollinators More important to Crop Yields than Fertilizer
"The critical importance of pollinators is exemplified in a recent study out of the University of California, Berkeley. Not only do pollinators help increase crop yields, they may be even more important than fertilizers, according to the study suggests."
"Scientists concluded that an almond tree can compensate for the lack of nutrients and water in the short term by storing the nutrients and water in the fruits instead, but cannot compensate for insufficient pollination"
Ecologist Alexandra-Maria Klein, Ph.D. and her colleagues at UC Berkeley found that when there is a lack of pollination, via bees and other pollinators, there is a stronger reduction in harvest yields than when there is a lack of either fertilizer or sufficient water for the crops. Their results, which were published in the journals Plant Biology and PLoS ONE, found that when crops were pollinated, the plants bear more fruit along with a change in their nutrient content.
What to Plant and WHY?
The simplest way to increase crop yields is to encourage pollinators to your garden. It's simple to do, easy to grow and eco-friendly.
BASIL and BORAGE produce flowers and are both companion plants for Tomatoes, Peppers, Squash and Eggplant.
Marigold is another companion plant AND it deters nematodes!
MILKWEED is the perfect addition if you're looking to attract Bees and Butterflies.
HERBS: Lavender, Lemon Bee Balm, Anise Hyssop, Caraway, Chives, Chamomile and Yarrow are all Flowering Herbs and what I call "Double Duty Herbs." These "double duty" varieties encourage pollinators to your garden AND are useful in herbal home remedies as well as home-cooking recipes.
SUNFLOWERS are an excellent addition to your garden for the bees and other pollinators. For multiple flowers, try Mexican Sunflower!
Nasturtium is another edible flower that attracts pollinators. Pretty flowers with a delicious flavor! As a companion plant, Nasturtium deters Squash Vine Borers!
For a detailed list, read