Q I’ve come across ethical or Fair Trade underwear, but I’ve never found any bras. Can you help?

A First, some reassurance. Teaming ethical knickers with bog-standard bras and daring to go out in mismatching underwear is hardly a green crime. There are much worse ways to be eco-inconsistent; it’s not as if you cycle to work but spend the weekend in Madrid.

But I understand your desire for an eco-friendly lift. Cotton, used in bras, is one of the most heavily sprayed crops around. Roughly a quarter of the world’s insecticides is poured on to cotton fields each year, with about 150g of it being used to cultivate one T-shirt.

For organic alternatives, Greenfibres ( greeenfibres. com) sells bras as well as pants. Its range includes a pretty floral bra (£27.50). For an even slinkier – but sadly pricier – option, the Brighton-based designer fashion label Enamore has launched a range of bras handmade in the UK from eco-materials such as hemp ( enamore.co.uk; from £42).

Meanwhile, anything made from bamboo gets the thumbs up in green circles. It’s the ideal sustainable material; a grass that needs no replanting, grows without fertilisers and pesticides, and can be harvested every three to five years.

Used in bras, I’m told, texture is no problem; the fibres can be made as soft as cotton. So let me introduce Hanro’s bamboo-blend bra ( figleaves.com; £24). Later in the summer it will be joined by an eco-bra designed by Chantelle lingerie, also using bamboo fibres and the bare minimum of chemical treatments ( chantelle.com). All of which suggests that greening our undies is becoming a national pursuit.

Q My garden is attracting weeds. If I want it to be organic, should I leave them alone?

A Not necessarily. A laissez-faire attitude to weeds in my urban garden would have seen off the broad beans long ago, strangled by the bindweed. It’s sinister stuff, winding its way around any plant in its path, stealing light and soil nutrients.

But not all weeds need controlling, according to the Times gardening editor Annie Gatti. “Many encourage a variety of wildlife, which in turn helps to create a balance of species in the garden,” she says. “The only ones that are a problem are those that are so vigorous that they take over, such as couch grass and ground elder.”

To find out which wild flowers provide habitat for which creatures, Gatti recommends Jenny Steel’s new book Wildflower Gardening (Webbs Barn Designs; £9.50). For pernicious weeds that blossom at the expense of your lovingly tended plants, my advice is to arm yourself with a hoe and uproot them.

The founding principles of organic gardening are boosting the natural health of the soil, working with nature and choosing the right plants for the conditions in your garden so that you’re not tempted to wage chemical warfare when things go wrong, according to Garden Organic (gardenorganic.org.uk).

But remember: one man’s weed is another man’s supper, seized upon by Hugh Fearnley-Whittingstall wannabes and turned into soup. As the old adage goes: “A weed is just a plant in the wrong place.” That they are proliferating in your patch at all is a good sign. It means that the soil is fertile. Feel flattered that you have created an environment in which so many plants want to make their home.

For Anna’s e-mail address and Eco-Blog, timesonline.co.uk/ecoworrier

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