Some of those lovely looking plants in shops contain a worrying amount of pesticides, environmental groups are warning. That is especially concerning for those who are looking to buy sunflowers and lavender in hopes of boosting insect health, the research by German environmental group BUND and Austria’s Global 2000 shows. Bees are dying for a range of reasons, from pesticides to drought, habitat destruction, nutrition deficits and air pollution, according to Greenpeace. But many plants marketed as being helpful for bees are actually harmful, say testers who assessed 44 bee-friendly plants in G…