INTERNATIONAL KIDNEY POTATO

By David Marks
The International Kidney potato is the variety which, when grown on Jersey, is more commonly known as Jersey Royals. International Kidney can be grown anywhere in the world with the correct conditions however Jersey claims to have some very specific conditions which make potatoes grown on their soil very special.This is a second early variety when grown under normal conditions although if left in the ground for longer it will bulk up to become a very acceptable maincrop potato.

PARENTAGE

The parents of International Kidney are not known.

APPEARANCE, TASTE AND CHARACTERISTICS OF INTERNATIONAL KIDNEY

The International Kidney Potato

Key to this variety, when grown as a new potato, is the extremely thin skin which is kept on when boiled. Boil them when picked early, they have an almost buttery taste which few other varieties can match.

They also do well if left in the ground for a month or so longer when they bulk up to a floury maincrop potato which is good for roasting, chips and wedges but no longer so good for boiling.

POSITIVE POINTS FOR INTERNATIONAL KIDNEY
Taste is excellent and quite distinctive. They make excellent early potatoes which can be left in the ground for two months to be harvested as a maincrop.

NEGATIVE POINTS FOR INTERNATIONAL KIDNEY
Generally poor disease resistance but grows quickly so often this is not normally a problem unless you want to grow it on as a maincrop.

BUYING INTERNATIONAL KIDNEY SEED POTATOES

International Kidney is not a particularly common variety of potato but is readily available online and occasionally in garden centres.

We recommend buying your seed potatoes from certified suppliers because those sold in supermarkets for consumption can be a source of disease and pest. We would avoid buying them from online general retailers such as as Amazon or E-bay unless you know exactly who is supplying the seed potatoes.

Buying seed potatoes from the discount store can be a good deal but it can also result in a sub-standard crop. The discount stores take the second quality seed potatoes whereas the more specialist suppliers take the best quality. Unfortunately you will only find this out after you have carefully tended your crop for several months.

Crocus (a GardenFocused approved supplier) sell International Kidney seed potatoes (and many other varieties) which are not only correctly certified but they are graded by size to avoid unduly small seed potatoes being sold. Click here for more information and to buy International Kidney online. A 2kg bag will contain about 22 good sized seed potatoes.

ALTERNATIVES TO INTERNATIONAL KIDNEY POTATOES

The key qualities of this variety are flavour and their ability to grow on as a maincrop if needed. On the basis of taste Arran Pilot is a good alternative. Charlotte also has very good flavour and at the same time will grow on in the ground as a maincrop if not harvested.

For other potato varieties which we have fully reviewed, click the drop down box below, select a variety and then click the More Information Button.

The planting and harvest dates used below are correct for the UK average. If you want them to be even more accurate and adjusted for your area of the UK click here. It only takes a minute and the adjustment affects every date in this site and lasts for six months.

WHEN TO CHIT / SPROUT INTERNATIONAL KIDNEY POTATOES

We recommend that you start chitting / sprouting International Kidney potatoes in. the third week of February This will give them four to five weeks to develop healthy sprouts just at the time when they are ready to be planted out. Keep the potatoes in cool but light conditions to ensure they grow short, green sprouts. Click here for our page dedicated to chitting / sprouting potatoes in the UK and Ireland.

WHEN TO PLANT INTERNATIONAL KIDNEY POTATOES

International Kidney are second early potatoes and they are ready for harvest, if conditions are correct, 15 to 17 weeks after the seed potatoes are planted. They can be left in the ground for a month or two longer and then harvested as a maincrop. The key factor governing the time for planting all potatoes is the date of the last frost in your area. Even a touch of frost can damage potato plants if their foliage is above ground, an unexpected severe frost can kill them completely.

The date for planting International Kidney potato seed can be calculated on the basis that seed potatoes will take four weeks before they appear above ground. Given also that you want them to appear above ground only when the danger of frost has passed (the last week of April is the UK average ) the last week of March is about right time to plant them.

WHEN TO HARVEST INTERNATIONAL KIDNEY POTATOES

The harvest date for all potatoes is not only dependent on when you plant your seed potatoes, it also depends on the weather conditions throughout the growing season. But on average you can expect your potatoes to be ready for harvest some time between the second and last weeks of July in your area of the UK.

PEST AND DISEASE RESISTANCE OF INTERNATIONAL KIDNEY POTATO

The table below sets out how good or bad International Kidney potato plants are at resisting common pests and diseases in the UK. The 0 point is average with minus (red) values showing lower than average resistance and plus values (green) showing higher than average resistance.

	-5	-4	-3	-2	-1	0	+1	+2	+3	+4	+5
Late blight – foliage
Late blight – tubers
Common scab
Powdery scab
Slugs
Potato Cyst Nematode (pallida)
Potato Cyst Nematode (rostochiensis)
Blackleg
Splitting
	-5	-4	-3	-2	-1	0	+1	+2	+3	+4	+5