Somehow or other, the number of potatoes I grow seems to creep up each year. I don't know how that happens, do you? ;-) This year I have 28 pots of them. Mostly they had one seed-tuber each, though the largest ones had two.
|These late-planted Pink Fir Apple ones could really do with earthing-up again!|
When I say "pots", I don't necessarily mean purpose-made flower-pots; almost any container will do, as long as it is over a certain minimum size (I suggest 10" - 12" diameter). For instance, I use a lot of the big plastic drums in which pelleted chicken manure is sold. Don't forget that it will need some drainage holes.
So, how do you know when your potatoes are ready for harvesting? Unlike most veg, with potatoes you really want that foliage to die down, so when it does, don't go thinking "Oh no, my plant has died!", but instead stand by to collect the harvest. Good strong foliage means that lots of solar energy is collected by the plant, and via the magic of photosynthesis much of it will go into producing those lovely tubers. It is generally reckoned that when the plant begins to flower there are tubers forming down below, but it is best to be patient and wait until the foliage (technically known as "haulm") dies down. It will wilt and turn yellow, and then eventually brown.
|These are "Swift" planted 22 March, harvested 25 June.|
The official harvesting guides given in the Thompson and Morgan catalogue are:-
First Earlies - 10 weeks from planting - i.e. usually from late May
Second Earlies - 13 weeks from planting - i.e. usually from July
Early Maincrop - 15 weeks from planting - i.e. usually from early August
Maincrop - 20 weeks from planting - i.e. usually from September
Of course there are very general guidelines, and harvesting times will differ according to plant variety. For instance not all Second Earlies will be ready at the same time. And people's views on the ideal size of a new potato vary too. When growing to produce new potatoes (i.e. the Early varieties, as opposed to Main Crop), I am looking for tubers about the size of a hen's egg. If you let them get much bigger than that they may be coarse and less delicious to eat.
If you are impatient you could always have a furtive "furtle around" in the pot with your hands, gently feeling for the presence of tubers, and it is even sometimes possible to remove a few tubers without digging up the whole plant. When you judge the time to be right, (as I did today) the best method of harvesting is to spread out a tarpaulin or something similar and just up-end the pot over it, allowing you to extract the spuds.
Oddly, one of the plants only had three tubers - ths biggest ones in this batch - the remainder all came from the other plant. In my opinion the three big potatoes are a bit larger than desirable for "new potatoes", whereas many of the others are just about perfect. They are also completely smooth and blemish-free. No slug damage and no scab, so I am well pleased.
It's not a big harvest, but look at it this way: two seed-tubers produced 22 useable tubers for eating. And then of course you also have to consider quality as opposed to quantity! We shall be judging that tomorrow night when we eat these potatoes as an accompaniment to some Duck breasts!