Rats and mice in summer: how to prepare

The best time to deal with rats and mice is before they move indoors, and in Pretoria that means summer. Rodents don't disappear in the warm months; they spend them outside, feeding well and breeding. The more food, water and shelter your garden gives them now, the bigger the population that will be looking for a warm roof when the Highveld nights turn cold. A few changes between November and March make a real difference to what happens in May.

What rodents are doing in a Pretoria summer

From spring onwards, rats and mice have everything they need outdoors. Gardens are green, fruit trees are bearing, insects are everywhere, and summer storms keep water easy to find. They nest in compost heaps, wood piles, dense creepers, under sheds and in burrows beneath paving. With plenty of food, they breed through the season, and each litter can be breeding itself within a couple of months.

Summer also brings its own push indoors. Heavy afternoon thunderstorms can flood burrows and drains, and brown rats in particular will move to drier ground, which sometimes means under the floor of a garage, into a store room or along a stormwater pipe towards the house. So even in January, you might hear something.

Step 1: cut the food supply

• Fallen fruit. Figs, avocados, peaches, guavas and pecans are a feast for rats. Pick up fallen fruit every day or two in season.
• Bird feeders. Seed spilt under feeders feeds rodents as much as birds. Use a tray, move feeders away from the house, or bring them in at night.
• Pet food. Don't leave bowls outside overnight, and store bags of dog food and bird seed in sealed bins, not open bags in the garage.
• Compost. Don't add cooked food, meat or bread to an open heap. A closed compost bin is much less attractive.
• Bins. Keep lids closed and avoid leaving bags out the night before collection.

Step 2: take away cover near the house

Rats like to move under cover. A clear gap between their hiding places and your walls makes your house far less appealing.

• Move wood piles, bricks, old pots and building rubble away from the walls, and raise them off the ground if you can.
• Cut back creepers and ivy on walls. Roof rats climb them like ladders straight to the roof.
• Trim tree branches that touch or overhang the roof.
• Clear the clutter behind the garage and the gap behind the wendy house, two classic nesting spots.

Step 3: close the doors before winter

Summer is the easiest time to proof your house, because you can work in the roof without freezing and the rodents aren't yet trying hard to get in. Check for:

• Gaps where pipes, cables and air-conditioning lines enter the walls
• Broken or missing air bricks and vent covers
• Gaps under garage doors and outside doors
• Loose fascia boards and gaps under the bottom row of roof tiles
• Open roof vents and gaps around the geyser pipes

A mouse can squeeze through a gap you'd struggle to fit a pencil through, and a young rat isn't much bigger, so steel wool and mortar or mesh beats foam alone, which they can chew.

Step 4: look for early signs

Walk the garden every few weeks with rodents in mind. Fresh burrows under paving or at the base of walls, droppings near the bins or in the garage, gnawed irrigation pipes, and greasy marks along the top of walls all tell you rodents are active. Catching it in summer, when numbers are still manageable, is far easier than dealing with an established colony in July. Our guide on how to get rid of rats covers what to do if you find signs.

What people get wrong

The biggest one is waiting. People see the odd rat in the garden in summer, decide it's outside and therefore not their problem, and then find a family of them in the roof three months later. The second is putting loose poison around the garden. It's a risk to dogs, cats, owls and other wildlife, rodents can drag it somewhere unexpected, and it does nothing about what's attracting them. If baiting is needed, it belongs in lockable, tamper-resistant bait stations.

For complexes, estates and businesses

In complexes and estates, one unit's compost heap or bird feeder can feed rodents for the whole block. Summer is a good time for the body corporate to agree on a site-wide approach: proofing, shared rules on bins and feeders, and bait stations along boundaries backing onto veld, rivers or spruits. For restaurants, food stores and warehouses, a scheduled monitoring contract keeps bait stations checked year-round. Summer storms flood drains and outside areas, so it's not a time to let monitoring lapse. You can read more about our approach on our rodent control in Pretoria page.

What does preparing cost?

Much of it costs nothing but time: picking up fruit, moving wood piles, cutting back creepers and closing bins. Proofing materials are inexpensive, though some homes need help with roof gaps. If you already have signs of activity, a professional inspection and baiting programme is priced on the size of the property and how many stations and visits are needed. If it turns out you've only got a mouse or two in the garage, a couple of good traps may be all it takes.

If you want an expert to check your property before winter, we can inspect, point out the entry points and set up stations where needed. See mouse control in Pretoria or our rat treatments across Pretoria for more on how we work. We're SAPCA registered with 25 years of experience, and our treatments carry a 3-month guarantee. Call 012 012 5526, or WhatsApp us a photo of the droppings or burrows you've found.