When you build a brick wall to add to your landscaping, sometimes it is just right the way it is; other times the wall does not seem to fit in because it looks too new. Make your brick wall fit in with the rest of your yard by ageing it. Choose one of several methods that all work but have slightly different end results. Pressure wash the wall to clean it before applying ageing techniques.
The enzymes in yoghurt are what can bring that aged look to your brick wall. Doing this on a sunny, warm day is best since the heat will speed up the process. Using plain yoghurt -- the cheap brands work just as well as the expensive brands -- brush the yoghurt onto the wall. Allow the yoghurt to sit and work. Eventually, the enzymes will grow into an aged look on the brick wall. Don't worry about washing the yoghurt off as the next hard rain will take care of that. The longer the yoghurt can stay on the wall, the better result you will have. Yoghurt works best when you have a small brick wall to age.
Chunky Compost Tea
For larger projects, without using chemicals, mix up a batch of chunky compost tea, and liberally brush that on the wall the same way you would the yoghurt. Compost tea consists of items from your compost pile, such as yard clippings, shredded newspaper, kitchen scraps and manure. Mix all these together, and allow them to decompose for a month or so, depending on the weather. They will decompose faster in warmer weather. Keep mixing the ingredients to keep them decomposing. After a month, add the compost to a large barrel, and cover with water. Cover the barrel, and allow the mixture to ripen for a week. Mix it every day. While the mixture is still chunky, brush this onto the wall. Allow the brick wall to sit until the next rain. Add more of the compost tea mixture to further age the wall after a rainfall.
Buttermilk works much the same as yoghurt to age your brick wall. Brush the buttermilk onto your wall, and allow it to sit without washing it off. The acid in the buttermilk will create mould and lichens that will add to the aged look of the wall.
Acids in many products make things look older or help them to break down faster. Create your own mixture to help age your brick wall. This mixture is a little less expensive than the yoghurt or buttermilk, and you can make the necessary amount you need without too much trouble. Mix milk and any acidic vinegar together, and allow the mixture to sit until it is lumpy. Add 1 tbsp of vinegar for every 1 cup of milk. Brush this on the wall, and allow it to work.