1 cultivate the soil – the root is going to have to push its way down through the soil so give it a head start by lifting the soil with a fork or digging it over, particularly in heavy clay soil. They are relatively tolerant of a wide range of soil pH.
2 start with seeds – you sometimes carrot or beetroot seedlings for sale in the shops but I don’t know why as you have to start from seed to be successful.
3 beat the weeds – some people wait for the first crop of weeds to grow, pull them out and then sow their root vegetables. I use a 1cm layer of potting mix to help keep the weeds down and give the seeds a good growing medium.
4 sow in a grid – sow 32 seeds in a 30cm square, two seeds at each of 16 positions (4×4). If you want baby veg you can sqeeze in 25 (5×5). Carrot seeds are tiny so don’t let them blow away. A few minutes sowing a few seeds carefully saves lots of time later thinning out. Beetroot ‘seeds’ are a group of seeds in a corky husk so just use one at each of the 16 positions.
5 keep moist – radishes and turnips will be up in a flash but carrots can be slow to germinate so you may need to keep them moist for up to a fortnight before you see seedlings. Slugs and snails can be a problem in wet weather. Keep larger pests at bay with some physical protection.
6 thin and weed – once they’re up, thin out any where both seeds have germinated. Nip off the top of the unwanted seedling so you don’t disturb the one you want to keep. Don’t worry about any gaps. Pull out any weed seedlings too. Sow another square of seeds so you’ll have a succession of root vegetables to pull.
7 minimal watering – roots can suck up water from relatively deep down in the soil. If you water them too much you’ll get lots of leaf and not much root.
The best way to find out if they’re ready is to pull one. You can poke around the neck of the carrot or beetroot first to see if it looks big enough.