Author Topic: Is fertilising potatoes after planting unnecessary?  (Read 453 times)

George the Pigman

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Is fertilising potatoes after planting unnecessary?
« on: June 21, 2022, 13:24:24 »
In never usually bother fertilising my potatoes after planting and have had bumper crops in the past although some years they are poor. In the latter case this can be usually put down to too much rain (rotting in situ or blight) or too little at the wrong time of year when the tubers are forming. I just make sure the soil is in good condition before I plant and add a bit of Growmore to the hole I plant the potatoes in. All the older gardening books I have never mention fertilising after planting.
Looking at the web a lot of sites nowadays enthusiastically recommend using granular fertiliser or tomato feeding several times post planting over the growing period, though in some cases they may have a vested interest as they are sites that want to sell you the fertiliser!
I would be interested in what people think of the issue.

Allotments 4 All

Is fertilising potatoes after planting unnecessary?
« on: June 21, 2022, 13:24:24 »

saddad

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #1 on: June 21, 2022, 13:56:29 »
My solution to possible poor yields ... is just to plant a few more.... I think they are just trying to sell more fertilisers to increase their profits... it is possible that newer varieties are bred for specific water/feed regimes to maximise or at least stabilise returns by agribusiness rather than older ones which could cope with a wider variety of conditions.

Beersmith

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #2 on: June 21, 2022, 17:06:35 »
From memory the recommended dosage for potatoes is an initial dressing of 4 ounces of growmore per square yard raked in before planting.  Depending on how generous you are when adding growmore to the planting hole you may be giving them a good start anyway.  Further feeding is recommended for maximum yields but we are keeping allotments not growing commercially, and this sort of decision is a regular issue. 
Not mad, just out to mulch!

Obelixx

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #3 on: June 21, 2022, 17:48:12 »
I added garden compost to the bed and then scattered a generous dollop of pelleted manure along the row before planting.   i don't feed after that.

The main problem is water here so, after the first lot of Charlottes I planted all grew huge and floury and the big baker/masher Bintjes failed completely, I  now only plant potatoes bought for the table and that have sprouted before i get round to cooking them.

This year that's some Grenaille and Noirmoutier potatoes and they're looking a lot happier after last night's downpour so i might have a firkle this weekend and see if any are ready to eat, before they go floury;
Obxx - Vendée France

Paulh

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #4 on: June 21, 2022, 20:40:43 »
I expect that mot of us do the same - prepare the ground and add a general fertiliser before planting. Potatoes need nitrogen initially to create the healthy top growth that will feed the tubers. A general fertiliser like Growmore (NPK 7:7:7) supplies that but the other ingredients may largely be washed away before the plants need them, to promote tuber growth. We then keep our fingers crossed on watering, rain and blight.

If you are going to feed for later, you need potato fertilisers that are high in the PK parts (the granular one our Association sells is 6:10:10), and I believe it can be add at planting or later as it is slow release. Tomato fertilisers are also high in PK, hence the sales pitches.

I never know when to water / not water my potatoes and would rather avoid creating blight conditions, so they largely get left to their own devices after I have (failed to) earth them up.

George the Pigman

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #5 on: June 22, 2022, 19:10:46 »
Thanks for your very interesting responses. I decided to bung a bit of extra growmore on and water with tomato feed as some of them were only a few inches  high  Mind you I only planted the lot, earlies and main crops at the very end of April!
We will see what happens!

BarriedaleNick

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #6 on: June 26, 2022, 09:32:37 »
In the UK I had spuds dialled in.  I dug a trench, added rotted manure and back filled with soil.  The earthed up with manure and tried to keep them watered well.  I only planted 20 maincrop spuds - Sarpo Mira - and they stood well into early October and could never eat all of the crop.  Struggling to replicate that here though - early blight is an issue and then getting enough water on them is pretty difficult.  They don't like the heat much and most people have already cropped them by now.  Still just getting enough but I may have to resort to some ferts next year..
Moved to Portugal - ain't going back!

Obelixx

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #7 on: June 26, 2022, 10:31:00 »
Barriedalenick - you may have to resort to growing just the small earlies.  It's what they do here on places like Ile de Ré and Ile de Noirmoutier.   The crop has been in the shops for a few weeks now and will soon be over.    Other potato crops here tend to come from cooler, damper regions of France or Belgium.

I tried growing Charlottes our first year here and planted them as I would in the Belgian garden but a bit earlier as it was warmer.  The whole let grew big but floury very quickly - more heat and not enough water for good salad potatoes.   The Bintjes I planted for baking and chipping failed completely.
Obxx - Vendée France

Tee Gee

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Re: Is fertilising potatoes after planting unnecessary?
« Reply #8 on: June 26, 2022, 12:56:24 »
My method was to prepare the potato bed as the planned bed became available at the end of the season(Autumn) usually I dug in 5 builders barrows of farm yard manure in a bed 30 ft long and 5 ft wide.

This was left to overwinter.

In Spring I would remove any weeds that may have appeared and rake in FB&B @ 4oz per sq yard.

Then I would plant out the tubers using a bulb planter approx 15” apart.

When the haulms we’re approx 6”-8” high I would earth them up.

That was it,till harvesting time. I never watered I left that to nature.

So to answer the question I only fertilised(fed) with a slow release fertiliser prior to planting out!