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When to Harvest Irish Potatoes

Irish potatoes (Solanum tuberosum) a term used to distinguish them from sweet potatoes, are indigenous to South America and never Ireland, in which they were a staple food. Potatoes are annuals that may be grown in U.S. Department of Agriculture plant hardiness zones 2 through 11. Depending on the number, potato vines will start to wilt and turn brown between 90 and 120 days after you plant them. This is the time to crop them.

The Way Potatoes Mature

Potato blooming is just a sign that potatoes are growing. New potatoes that have low starch and high water content grow from the next month. Since the potatoes get larger from the fourth month, their water content decreases, their starch increases and their skins thicken. Their dying vines will tell you that it is time to dig them up. Complete harvesting before freezing weather arrives if you have frost in your area.

Harvesting New Potatoes

Ancient or “new” potatoes, typically harvested when the plants start to bloom, are little, round and smooth. If you think you have a few of those potatoes close to the surface of a potato hill at its early stages, dig down with your hands, locate the sizes you desire and ease them from the dirt. The potato plant will keep growing and produce more potatoes. The National Gardening Association notes that if the soil is soggy, which makes it messy to eliminate the little potatoes by hand, it is possible to dig up the whole plant with a potato fork or digging spade. Harvest the potatoes that you want and put the rest back from the ground. Do this quickly because the potatoes shouldn’t remain in the sun for long or they’ll turn green and never taste great. Immature potatoes are going to have thin skins and are easily bruised. They lose water fast. If you attempt to store them, then they’ll turn soft and shrivel. They are also more prone to rot.


Like fresh potatoes, it is best to dig mature potatoes on a warm, dry evening that’s cloudy. If you’re growing many hills of potatoes, the very first hill you dig will tell you how deep in the hills that the potatoes are growing. Use a potato fork or spading fork to gently dig in one side of this hill and lift up, shaking dirt out between the tines. The potatoes must rest on top of this times. You may spear some potatoes together with the tines on the first hill but few or none on the rest of the hills. If you do spear potatoes, eat those that day. They won’t store.

Timing and Applications

Should you wait until the vines start dying and dig up a hill of mature potatoes, you’ll need a spading fork, occasionally known as a digging fork or a potato fork. Spading forks usually have four triangular tines with a flat surface on front. Some potato forks look like spading forks but have five to six tines. The tines with flat surfaces are utilized to lift potatoes from the soil. Another kind of potato fork has nine tines with dull finishes, designed not to hurt potatoes once you lift them.

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