How to turn your garden into a natural security barrier

Plants to use as security deterrents

Rambling Rose

Train a good, old-fashioned rambling rose with sharp thorns along the top of your wall or fence and no one will try to breech this vicious barrier. Give it a sunny spot to ramble wildly, feed it well and a single plant will easily cover 10 metres within a few years. For quicker coverage, space plants three metres apart. The bonus is the gorgeous blooms in late spring and, with the right feeding in February, you’ll get a second flush of flowers before summer is over.

Num-num or amatungulu

Num-num or amatungulu (Carissa macrocarpa) is an indigenous shrub with Y-shaped thorns and attractive, dark green, glossy leaves that can be trained into a dense hedge. It’s hardy, fast-growing, tolerates wind and drought well and grows up to two metres in coastal areas. Fragrant white flowers in spring are followed by red fruits rich in Vitamin C. The birds love them, but save some to make your own delicious jelly. As with most hedges, set plants about one metre apart.

Christ-thorn

Christ thorn (Euphorbia milii) is one of the prickliest multi-stemmed plants around. It doesn’t grow very tall, but can create a formidable wide, low barrier – or use it below a window. This hardy Madagascan native has pretty red or yellow flowers most of the year. It’s technically a succulent, so give it a sunny spot and it will grow to about a metre high and 45 centimetres wide. Plant a couple of rows quite densely to keep people and pets out. Note: the milky sap is poisonous!