Do not try to pull the parsnips out by hand – ease them out of the ground gently using a fork. Parsnips will be ready to harvest when the foliage begins to die down in late summer or autumn. Parsnips can be a good addition to a fruit orchard or forest garden – after harvest, leave a few parsnips in place to go to seed as parsnip flowers are beneficial to fruit trees as they attract a range of beneficial predatory insects. Like carrots, parsnips will do well when grown with alliums such as onions or garlic, as the smells can deter and confuse carrot fly and other pests. If you know carrot fly is a problem where you live then carrots and parsnips can be grown under covers of horticultural fleece or in raised beds with barriers. The only tack to take is to try to prevent one in the first place. Unfortunately, if you have a problem with carrot fly there is no way to remedy it. Try not to crush the foliage when weeding or thinning as this may make it more likely that your crop will be attacked by carrot fly. Be careful not to let the soil dry out and crust during this period or the small seeds may have difficulty breaking through. Even at these temperatures, seeds may take three weeks or more to germinate. Seeds germinate best when soil temperatures are 50F to 70F. Keep the soil evenly moist through the growing period to prevent the roots from splitting and weed carefully around the roots. Like carrots, parsnips like a deep, well-drained soil. Unfortunately, thinnings cannot be eaten or transplanted, so discard these on your compost heap. Thin parsnip seedlings to a spacing of around 15cm when they are 2-3cm high. The radishes will then be harvested before the slow growing parsnips need the space. The radishes will germinate and appear far quicker than the parsnips, which will take around three weeks to appear.

It is a good idea to mix in some radish seeds with your parsnip seeds to mark the rows and to make the most of the space. Sow your parsnip seeds thinly into shallow drills in a site with deep, fertile soil. Still, it is best not to wait too long since parsnips need a long growing season. In addition, parsnips take a long time to mature and may. Further north, it is usually better to wait a little as parsnip seeds are very slow to germinate in cold weather and all sorts of problems can prevent their growth if they are in the soil for too long before they begin to grow. This is because the parsnip plant grows very long and large roots which a pot may not be able to hold. You can sow parsnips in the soil where they are to grow from early spring – in the south of the UK even in late February. Parsnips can be eaten mashed, roasted or boiled in a wide range of different recipes and though they have a strong flavour, can be delicious when cooked well and combined with the correct flavours.

Parsnips are a versatile vegetable that, while they have now fallen out of fashion somewhat, were once a staple like potatoes are now. Parsnips require a big investment in terms of time and space but if you have a large enough polytunnel then you may like to grow some parsnips in it.

Growing parsnips