Kitchen Garden Forum

Over the last few weeks I have cleared my second early and maincrop potatoes and noticed something strange. My vegetable garden is divided into beds 10'x25' using concrete paths, I used one of these beds for these potatoes. There were 4 equally spaced rows with 17 or 18 seed potatoes per row, 2 rows of Charlotte and 2 rows of Maris Piper. The outer row of Charlotte yielded 42 Kg whilst the inner row only yielded 29 Kg. At the time I thought it was because the Maris Piper had grown very big tops and flopped over the Charlotte but I have now lifted the Maris Piper and got almost the same effect, outer row 63 Kg inner row 51 Kg.
Have I got the spacing wrong for best yield? What spacing do other people use?
PS : JB what is a good commercial crop rate? If I've done my maths right I've dug about 32 tons per acre average, 24 for Charlotte, 39 for Maris Piper.

Hi Geoff,
Commercially 20 tons to the acre is about average hereabouts. Main crop spacing 15" down the row and 33" twixt rows is the crop right next to me this year. (My land but not my Potatoes)
Do you think that the water run-off from the paths give your outer rows an advantage? Apart from that I have no explanation but will have a ponder.
JB.

Maybe the potatoes at the edge just have a little more space on that side and so produce more tatties

We use 30 inches between rows of earlies and 36inches between main crop rows, but I can't help with yield, never weighed them.
Do you earth your potatoes up? I wondered whether the outer rows probably had more earthing up than the inner ones which increased their yield?

I have always found the ones at each end of the row always have substantially more potatoes than the others.

I think it must just be competition - as OH says the end of a row often has a good yield but then again I often plant a good looking tuber at the end. The earthing up theory is also possible as the outer rows do get more attention. I don't think water off the paths would have an effect because the beds slope in the long direction.
I don't normally weigh them like this but I dug the first row of Charlotte one day and laid them out on the garage floor to dry, the next day when I put the second row alongside the difference was obvious so I checked the Maris Piper out of curiosity. I space by the simple method of buying a bag of each and fitting them into one bed. If I was a cat I would be dead!

Hi Geoff,
For obvious reasons I now do not grow main crop potatoes but my earlies, which are actually 2nd earlies, Maris Bard are grown in a designated raised bed and 25 spuds are fitted equidistant in an 8ftx4ft area with the ground underneath liberally manured and the seed spuds placed on that manure with about 6" of soil initially and the made up to 12" which compacts down to around 9". I have two such beds and they move from designated bed to designated bed to give me my rotation. I have designated beds which are 4ft wide and 33ft long which are not raised and the raised bed is simply
moved either up and down the bed or moved to another bed. It all sounds rather complicated be it is actually very simple. I use fresh soil every year in the raised beds.
JB.