Preparing to lift potatoes

If you’re growing a small number of potatoes and using them within a short space of time, then you can just pull up your tatties when they’re ready, clean them and eat then.

But if, like us, you’re growing enough maincrop potatoes to last a year then there’s a lot more work to do before you can lift them - not least if you have 400sq metres of potatoes as we do!

The first thing to decide is when you’re aiming to lift your maincrop. We want them all out before the first frosts hit in late September, so we want our crop lifted by the end of the second week in September - weather permitting.

Next, you have to allow a couple of weeks for the potato skins to set, helping the tubers store better and for longer. (Setting involves leaving the tubers in the ground with the haulms removed.)

And that calculation brings us to the last week in August, when I get to spend a couple of days work cutting all the haulms back.

I spent Wednesday clearing up the potato patch, cutting back weeds, removing stones that might blunt tools and earthing up any potatoes that were emerging from the ground. Thursday and Friday were spent cutting the haulms.

With the patch cleaned up, it was time to check the tools over: a tapner (a curved knife), crome (a draw fork), and a muck fork. A good scythe stone and/or a shepherd’s steel are also essential.

The tapner, used to cut the haulms, should be very sharp but not razor sharp. It should cleanly slice through a bunch of potato stems but not shatter nor dent if it hits a stone.

Alternatives to the tapner include a reaping hook (a serrated one is better as it requires less sharpening), a sickle or a scythe with a ditching blade. A scythe means less bending, but real skill is needed to walk in a furrow and smoothly take off the haulms along a high ridge.

To cut the haulms, you walk astride the ridge with a foot in the furrows on either side. If you’re holding the tapner in your right hand, you should walk so that the fall of the haulm (usually away from the prevailing wind) is to your left.

You can then pick up the haulms on one potato plant with your left hand, bunch them together and, with an almost vertical chopping motion, cut through them with one or two cuts. Watch what you’re doing at all times!

If you’re holding the tapner in your left hand, you’ll want to work the opposite way. And this is why it can get a bit awkward if you have several people cutting the haulms and one of them is opposite-handed to everyone else.

As you work your way along the ridge, throw the cut haulms into the next furrow over where, if you’re lucky enough to have helpers, they can be pulled away with the crone. If you’re on your own, then you’ll have to come back later and collect them.

At the end of each row of potatoes, stop and whet the tapner with your scythe stone or steel. This will give you a breather as well as put a fresh edge on the blade - which does dull quite rapidly.

I find a magnetised shepherd’s steel quickly restores a good working edge to the blade at the end of a row, while the scythe stone takes more time but gives a sharer finish. As a result, I use the steel three times, then the stone once, then the steel again.

With all the haulms cut and laid in the furrows, they can be dragged out with the crome. The aim is to remove the haulms without unearthing the potatoes so do not dig the fork into the soil, just drag the haulms to the end of the row.

After that, it’s time to get out the pitch fork or muck fork and stack the haulms ready for removal in your wheelbarrow, cart or trailer.

You can add the haulms to your compost heap and the heat should kill the spores of things like late blight, but the heap has to be active and hot.

With the cold weather fast approacing up here, our compost heaps tend to cool too much to take the chance and so we burn the haulms on a fast and hot fire built out of pine scraps.

And before you nip inside for a well-earned cuppa or glass of cider, there’s still two more tasks to do.

The first is to take a small hoe and carefully check all your rows for any potatoes that might have been unearthed. They all have to be covered with sufficient soil that it won’t be washed off by rain - and you should check after any rain just to be sure.

Any potatoes exposed to sunlight will produce solanine, a bitter and poisonous alkaloid. You’d have to eat a lot of potatoes to poison yourself, but it’s better to stop your potatoes from being exposed to the sun in the first place.

So, how do you tell if your potatoes have become toxic? The clearest indicator is when they turn green - this happens when the chlorophyll in the tuber is activated by sunlight - but potatoes can develop solanine without turning green. The second indicator of increased solanine levels is a bitter taste.

If the potatoes do turn green, you can often save some of the potatoes by either peeling them (most of the solanine is just under the skin as it’s ended as a defence against bugs) or cutting off the green bits.

They won’t store, well, not unless you cook them and freeze them, but you did want some fresh potatoes for your dinner didn’t you?

The second job before going in? Clean all your tools, sharpen them and oil them ready for their next outing.