Lavender

• Lavender, while basically untroubled by pests, provides midseason flowers for beneficial insect populations, including lacewings and syrphid flies. According to the University of Maine Cooperative Extension, many beneficial insects "like tiny flowers that offer both pollen and nectar."
  
  

Oregano

• Oregano, a hardy perennial, flowers in mid to late summer. Zorba Red offers white flowers, while ornamental Kent Beauty produces pink flowers and Hopley's Purple yields purple blooms. Oregano attracts nuisance and damaging insects when moved indoors, warns the Penn State Cooperative Extension. The extension lists spider mites, aphids and leaf miners among the pests that make indoor production of oregano problematic.
  
  

Bees

• Bees are attracted to flowering herbs, including oregano and lavender. Bees pollinate flowers, fruit trees and food crops. The Purdue University Extension lists lavender and plants of the genus Origanum, which includes oregano, as plants helpful in supporting a diversity of bee species. Lavender attracts bees in spring and summer and lavender honey can be found in the area of large, intense plantings of the flower, advises the University of California Cooperative Extension.
  
  

Syrphid Flies

• Syrphid flies, also called flower flies, sweat bees or hover flies, may be mistaken for wasps or bees, but these insects neither bite nor sting. They can be identified by their single pair of wings. Their larvae eat large numbers of aphids, while the adults depend on flower pollen and nectar. In exchange for food, the adults assist in pollination. According to the University of Maine Cooperative Extension, planting flowers will attract the flies to your home landscape.
  
  

Lacewings

• Lacewings are a beneficial insect. Green lacewings have an ethereal appearance, with green translucent wings. Lacewing larvae consume "soft-bodied insects and mites, including insect eggs, thrips, mealybugs, immature whiteflies and small caterpillars," according to the Texas A&M University AgriLife Extension. Adult lacewings feed on nectar and pollen supplied by garden flowers such as lavender and oregano. The University of Maine Cooperative Extension lists flower spikes among the best flower structures for beneficial arthropods.