Mould has likely grown because of damp conditions and a warm interior. The weather has been switching from fairly cold to mild in the last few weeks so if it got at all damp inside then when it heated up during the day, mould will have started to grow. The first thing we'd recommend is moving the car into the sun if you haven't already, but make sure you wear a dust mask - mould is no joke and can make you quite sick depending on which type it is. Open all the windows and doors to air out the car next time it's a warm sunny day, which you need because mould can’t grow in dry conditions. Next, check anywhere else that there could be mould (carpets and flooring, in all the corners etc).

If you plan to clean it yourself, you have to be very thorough and ensure that you're wearing a mask and gloves. You can use a toothbrush to break up larger mould clusters if there are any and a vacuum to suck up some of the rest, but make sure you throw away the vac bag or empty the canister immediately after. White vinegar is a good treatment for mould as it's acidic and will kill it, so mix a distilled white vinegar and water solution 70-80% vinegar) and put it in a spray bottle for the easiest application. Spray all the mouldy areas and then let it dry completely. Vacuum up what's left and ensure nothing is left damp. To prevent mould from coming back, get all possible leaks repaired to stop the interior from getting damp, look into getting a dehumidifier if damp is a regular issue too. If you have a garage for a dehumidifier - we like Meaco's products. We reviewed one on Honest John Kit, so you can have a read of that and make a decision from there once you've done some extra research: kit.honestjohn.co.uk/reviews/review-meaco-dd8l-zam.../