Nothing can quite compare to the taste of new potatoes, especially when they’re homegrown. This humble tuber takes a while to mature, and all the magic is happening below the soil’s surface. Lift potatoes too soon, and you might get tiny ones, or leave them in the ground for too long, and they may start to rot.
If you’re a beginner gardener, you’ve probably asked yourself how to know when potatoes are ready to harvest. There are quite a few signs you should look for before starting to dig potatoes, and this is what we are going to cover today.
When looking to harvest potatoes, you need to differentiate between first early, second early and maincrop potatoes, each with its specific harvesting time. Always check the weather and observe the plant’s foliage. If it’s already flowered and the leaves are yellow, it’s nearly time for harvest.
There’s no clear-cut answer on when to harvest potatoes, but the good news is that you can always reach inside the soil, dig out some of the potatoes and check how they’re growing. As you’ll grow more varieties, you’ll have more experience to tell the difference between normal growth and diseased plants.
In this article, we’re going to explore the difference between first earlies, second earlies and maincrop (or storage) potatoes, how flowers and wilting foliage can be an indicator of plant maturity, how to harvest potatoes and other FAQs you may find useful.
Let’s dig in! (Pun intended).
Harvest your mature potatoes according to their DTM (days to maturity)
Not all seed potatoes are created equal. If you’re not already familiar with the three main seed potato’ types, now is the perfect time to learn about them.
So how long do potatoes take to grow according to each variety?
- First early potatoes – Sow in late March. Harvest potatoes after approximately 90 days – late June or early July.
- Second early potatoes – Sow in mid April. Harvest potatoes after approximately 110 days – July and August.
- Maincrop potatoes – Sow in late April. Harvest potatoes after approximately 135 days – in fall within August to October.
Keep in mind that your harvest time depends on the weather – mark your sowing day on the calendar to know how much time has elapsed. If the weather has been cold and rainy, the potatoes may take a longer time to mature, so take that into account as well.
When sowing your potatoes in spring, chitting them may give you a head start, especially if you’re looking to grow fast-maturing early potatoes.
Another thing to consider when growing first and second early potatoes is to harvest them before blight conditions appear – check the weather for rainy periods and get them out of the ground before the blight gets them in July or August.
Don’t worry, you can still save some of your blighted potatoes for consumption, but it’s best to avoid blight if at all possible.
Growing first early and second early potatoes is great for a small garden because it allows for a second crop to go in after harvest. Check out this article to find out what to plant after potatoes.
Flowers can be a sign you can dig up your first potatoes
Your crop may not be ready for harvest, but you can still get a plate of delicious baby potatoes every now and then before the plants completely mature.
In fact, you can reach underneath the soil with your gloved hand and “steal” a couple of potato tubers without hurting the potato plant or the rest of the potatoes.
Flowers are the best indicator that new potatoes are starting to form, and they’ll soon be ready for harvest. Not all potato varieties flower in the same way, and some won’t flower at all, but if you notice flowers forming, harvest time is near.
Potatoes are usually ready to harvest about two weeks after they have finished flowering. However, the exact timing can depend on factors such as the variety of potato, weather conditions, and planting time.
When a potato plant flowers, the new tubers will be about 2 inches in diameter, and they will continue to swell as the flowers turn into fruit. The new potatoes will have thin papery skin that you don’t need to peel – in fact, they’re much more delicious with the skins on.
First early and second early potatoes also don’t need any curing period, as they’re meant to be consumed right away. They will store for a couple of months, but not much longer than that. The main advantage to these potatoes is their timing – they will be ready for harvest much sooner than maincrop or storage potatoes.
Plant foliage is the best indicator of when to harvest potatoes
When the days to maturity have passed, you will notice the potato plant’s foliage starting to turn yellow, wilt and die back. If this is happening during the expected time for harvest, it’s normal, and it’s not a sign of blight, wilt or other diseases.
Early potato plants will start wilting as soon as July, while maincrop potatoes may take as late as September or October.
When you harvest early potatoes, you should know that they are best consumed right away, as they don’t do as well in storage as maincrop potatoes. You don’t have to do anything special in terms of curing or storage, and you can harvest them whenever you need a fresh meal.
With maincrop potatoes, you need to be a little more intentional. The best time to harvest maincrop potatoes is when the foliage has died back, and their skins have toughened. The best way to check this is to lift one potato plant and feel a tuber’s skin. If the skin still feels thin and translucent, it’s best to leave them in a little longer and check back within a week or so.
Don’t leave potatoes in the ground for too long, though. When the potato plant has completely died back, the potatoes underground are at the risk of rotting, so harvest them as soon as possible because they won’t continue to cure underground.
Don’t wash the potatoes. Spread them on a dry surface, sheltered from rain and allow them to cure for at least 7 days. You can do this in a garage or a root cellar before storing them in bags or boxes.
Three ways you can harvest your potatoes:
Now that we’ve talked about the right timing for harvesting potatoes, let’s learn about the best way of lifting potatoes so that we don’t harm their skins:
1. Using your hands
This method works best if you’re gardening in a small area, using buckets, grow bags, or raised beds.
- You can find our recommended containers for growing potatoes here.
- You can find our recommended grow bags for growing potatoes here
With buckets and bags, simply lift the potato plant (you’ll see small potatoes hanging from the roots), and turn the bucket or bag upside down inside a wheelbarrow. Pick the potatoes and discard the soil in the compost bin or put it back on your garden beds.
Inside raised beds, if your soil is fluffy and light, you can do the same thing and look around, feeling for tubers. This method is perfect for occasional harvests before the potato plant is fully mature because it allows the other potatoes to keep growing.
2. Gently using a hand trowel
Using a hand trowel is another way to look for potatoes inside your raised beds if the soil is a little firmer. Be careful not to scrape the skins off potatoes, and stop digging when you feel like you’ve reached a tuber. Ideally, it would be best to dig a perimeter around the potato plant to loosen up the soil and then use your hands for harvesting potatoes and check for hidden tubers.
3. Using a spading fork
A spading fork is the best tool for digging up potatoes. Use it away from the plant, push down and lift the entire potato plant – tubers and everything.
Using a spading fork works best when you’re harvesting long rows of potatoes. You could also use a shovel (my parents have done this for decades), but you risk cutting some potatoes which won’t store as well as the intact ones.
Do I need to be hilling my potatoes?
Hilling potatoes also called mounding or earthing up, isn’t really necessary. To be honest, I’ve never hilled my potatoes, and I’ve always had good results. The purpose of hilling is to avoid getting green potatoes (which might happen if they’re exposed to sunlight).
Traditionally, potatoes are planted in rows, and when covering them with a shovel, farmers form a natural hill. In raised beds, however, you cover them by hand, and there’s really not much room to hill them. If you’re worried about your potatoes being exposed to light, you can start mulching your potatoes with straw and keep adding mulch as they grow.
My potato plants are dying. Is it blight or are they ready for harvest?
If you notice your potato plants wilting during the summer months, depending on your potato variety, they could very much be ready for harvest. The simplest way to get your answer is to dig up some potatoes and check them for damage. Whether it’s blight or they’ve matured, once the potato plants are dying, there’s no point in keeping the potatoes in the ground much longer.
If you live in a tropical or subtropical area, bacterial wilt can cause a lot of damage to potato crops, especially during rainy seasons.
Potato blight, the same disease that caused the great Irish famine, is a late blight that mainly affects potatoes and tomatoes and can destroy crops in as little as a week.
You can differentiate potato blight from a plant that’s ready for harvest by examining the foliage – if you see dark brown blotches, shriveling and rotting leaves, then potato blight is most likely to blame. The only thing you can do is pull the plants out immediately, so it doesn’t spread to neighboring plants.
Can I eat potatoes right after harvest?
Yeas, you can eat potatoes right away. You don’t need to cure freshly dug potatoes before cooking them. The purpose of curing is to increase shelf life when storing potatoes. In fact, first early and second early potatoes are most delicious when cooked and consumed right away.
Tubers are the only edible part of a potato plant – stems, foliage, flowers and fruits are all poisonous.
Why are my potato plants too small / too tall?
Potato plants vary a lot in terms of height, depending on their variety. I have three varieties in my raised bed, each with a different type of leaf, flower and height. So how tall a potato plant gets has a lot to do with what variety you’ve chosen to grow.
But sometimes, potato plants can grow too tall because of other factors, like excess nitrogen, which causes a lot of foliage growth and a smaller crop of potatoes. Potato plants that are too tall are also in danger of falling over in windy conditions and snapping their stems.
Potato plants that are too short can grow this way because of their genetic characteristics, but it could also mean that they’re not getting enough sun or that the soil can have traces of herbicide, which could stunt their growth.
Why didn’t I get any potatoes?
Another common grievance when growing potatoes is a mediocre harvest – small potatoes or no potatoes at all. This could happen for several reasons. Your soil might be too rich in nitrogen, which causes most plants to grow lots of leaves but not a lot of fruit. Try testing your soil to find out if this is the case.
Another reason for not getting any potatoes is digging them too early or planting maincrop potatoes instead of early potatoes. If you’re digging your main crop potatoes in July, the plant is green and healthy and shows no sign of dying back – are you sure you’re not looking for potatoes too soon?
How to select seed potatoes
If you’re planning on growing potatoes from your own harvest, it’s important to select the right seed potatoes. You want to choose potatoes that are healthy and free of disease, so look for ones with smooth skin and avoid any that have already sprouted or have rough, scabby skin.
For best results, go for medium to large potatoes that have plenty of energy to sprout and grow. In my experience, medium size works best, and you can cut up the larger potatoes. However, try not to use very large potatoes for seed, as they can lead to overcrowding and reduced yields.
Once you’ve got your them all selected, store potatoes in a cool, dark place until it’s time to plant them. This will help prevent them from sprouting or rotting, so that they’ll be in good shape when it’s time to plant them.
Knowing when your potatoes can be harvested is a thing of trial and error. You can learn a lot about this plant by simply digging every couple of weeks and observing the stages of development.
Getting the right harvesting time will depend largely on the variety of potatoes you’ve chosen, as well as the outdoor temperatures. Hopefully, the information above has served you well – now it’s time to go in the garden and check your potatoes. Have they flowered? Are they wilting? These are all signs this exciting summer crop is almost mature.