Chitting (sometimes known as sprouting) potatoes is one of those practices handed down through the generations that appears to encapsulate the mysteries of gardening. It's one of the jobs that gardeners will do without question but when you ask them why they do it - most of them won't have an answer.
Compared to the potatoes natural habitat of 'sub-tropical' South America, the English climate isn't perhaps the first place you would think to grow these staple crops, but with centuries of selective breeding the modern potato now does very well in our soils. There is one problem though that still remains and that is our comparatively short growing season and this is where the art of chitting comes in.
There are other advantages to breaking the dormancy by chittings as modern early cultivars will crop far earlier and more heavily. You can help the process further by rubbing off all but the four strongest sprouts so that the tuber's energy is diverted into a few really strong shoots that form the new potatoes as early as possible. Second early and maincrop potatoes also benefit from chitting but they don't need a thinning out of the sprouts. Chitting late cropping varieties will result in them producing their foliage earlier and hopefully produce new potatoes before being hit with infections of potato blight or problems with summer droughts. Again, they will mature earlier and can be gathered before slugs do too much damage the tubers.
If the weather is unsuitable at the time of planting then you can remove all of the sprouts and start again. Also, if you have positioned some of your potatoes upside down and the potatoes sprout from the wrong end, simply rub off the sprouts and turn the potato the right way up. Keep them where they are while the shoots are developing and they can stay there until they are ready for planting later on in March.
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