Why now is the best time to plant potatoes for Christmas

August and early September is the time to plant potatoes to be sure they’ll be ready to harvest for your Christmas dinner.

Because temperatures are already warm by late summer, there is no need to ‘chit’ (or sprout) the seed potatoes before planting – they can be planted directly into the soil. Ideally, potatoes for Christmas should be grown in growing bags or large pots as they will need to be moved to a sheltered position before the first frosts arrive.

The best types of potatoes to grow for Christmas are first or second earlies. Suitable varieties include first earlies ‘Lady Christl’, ‘Orla’ and ‘Rocket’, and second earlies ‘Charlotte’, ‘Maris Peer’ and ‘Twinner’, but there are plenty of others to choose from.

The most important factor when selecting potatoes to grow for Christmas is that they have been ‘cold-stored’. “If you take a potato that you have just grown and stick it in the ground, it won’t sprout,” Smith explains. “You need to buy ones that have been kept in a cold store in order for them to grow at this time of year.”

Smith suggests growing Christmas potatoes in pots rather than directly in the ground so they can be moved somewhere sheltered before the frosts arrive. “I use a bucket with drainage holes that is at least 40cm (16in) diameter and 40cm (16in) high,” he says.  

“Fill the bottom of the pot with 10cm (4in) of a general-purpose, peat-free compost. It is best to use fresh, bought compost rather than homemade or older compost, as this avoids problems with introducing slugs – particularly keel slugs. We’ve got lots of tips for keeping slugs out of the garden.

Smith places two or three potatoes into each pot. As he explains: “The more potatoes you put in, the smaller the potatoes will be. Place potatoes on the surface of the compost spaced equally apart.

“There is no need to gradually earth up the potatoes with more compost as they grow, as you would with conventional potato growing,” Smith continues. “Simply fill the container right to the top with compost. The advantage of this is that you will get bigger potatoes, albeit a smaller quantity.”

Place the pot a sunny position and occasionally water when the compost feels dry to the touch. Before the first frosts arrive, move the pot into a sheltered position such as a porch, conservatory or frost-free greenhouse. Smith says he moves his pot of potatoes into his shed as autumn approaches.

“Even if the plant stops growing and the foliage starts to die back, the potatoes can happily stay in the pot until you are ready to harvest them for your Christmas dinner. I trim back the foliage at this stage and reduce watering, then allow the potatoes to mature in the shed until I’m ready to eat them. ”

Potatoes should be ready from late October/early November.

Smith says: “The simplest way to harvest your delicious potatoes is to stick your hand in the compost and pull out a few potatoes. Keep the remainder under the soil until you need them again. By keeping them dry and frost-free, they will store in their container until Christmas and longer.”

We also spoke to RHS horticultural adviser Rebekah Mealey for her tips on growing potatoes for Christmas.