potatoes growing in a plot late in the year with trees with no leaves on them

How Late Can You Plant Potatoes: seed to harvest

Potatoes can be planted as soon as the ground becomes workable in early spring. Usually, by mid-February you can get out and prepare the soil for planting.

Potatoes will not grow until the soil temperature has reached 45F so when you plant them you will need to be patient until the soil warms to this temperature and beyond.

I always find an important thing to look for at planting time is that the soil is well-drained and does not become waterlogged as the potatoes will rot if they are planted in water-saturated soil.

How to grow potatoes

Before i begin to delve deep into this article, if you would like more information about growing your own potatoes, please read my article How to grow potatoes, This covers everything you need to know from planting, preparing seeds, growing, harvesting and storage and more about this great vegetable.

What is the best soil for growing potatoes

I find the best soil for growing potatoes is a free-draining deep loam soil high in organic material with a pH of 4.8 to 5.5. You should get a soil test done for NPK if you want the best chance of growing a good crop of potatoes.

Clay soils are prone to waterlogging or drying out and very sandy soil can also dry out quickly leading to scab on the potatoes. You can upgrade your soil by adding the minerals or soils you are lacking. For example, if you have very clay soil in your vegetable garden you could upgrade it by adding more shells, sand, and organic material like manure or compost and then rototill it through.

The shells and sand will help prevent the clay soil sticking in a mass and the organic material will help add nutrients and also fluff it up a bit.

Preparing seed potatoes for planting

Two to three weeks before I plant my seed potatoes in the ground, I put them into a wooden box and keep them somewhere warm – like a garage or shed.

Over the next couple of weeks, small buds will appear on the seed potatoes which will grow and turn green. It is important to keep the seed potatoes in the light because if they are in the dark the buds will be white, not green and they will be very fragile and easily broken.

Once the buds are ½” to 1” long they are ready to take out to the garden and plant.

Can you plant potatoes in the full

You may have read or heard people talking about cutting up potatoes to use for planting. The reason for this is usually to save money.

Normally one potato will have multiple buds on it- maybe 6 or more, so some people if they don’t have enough small whole potatoes (known as seed potatoes) will cut up a large potato into 2,3 or 4 pieces which will give them 2,3, or 4 seeds from one potato.

There is no benefit to cutting large potatoes versus planting a single whole small seed – it is just about not wasting potatoes.

How deep do you plant potatoes in the ground?

Depending on where you will be planting your potatoes – I always advise planting potatoes in drills as they are less likely to become waterlogged than in a bed or a container.

I would dig down 4 to 6 inches (or the mid-way point in the drill) and place the seed into the ground with the buds facing upwards and then gently fill in the loose soil back in over the potato.

How far apart should you plant potatoes?

I would plant the next potato along every 14 inches. The closer you plant your potatoes the smaller they will grow and the more space you give them the bigger they can grow. Of course, there are limitations to this.

If you plant the potatoes every 24 inches you will be wasting ground and if you don’t have enough fertilizer or manure they won’t grow as big either.

You could have larger potatoes planted 14 inches apart on well-fertilized soil and another drill of potatoes planted 16 inches apart and end up being smaller because they didn’t get enough fertilizer.

How long does it take to grow potatoes?

Usually, from when a seed potato is planted it takes around 100 -120 days for the crop to be ready to harvest and eat. There are exceptions to this generality such as: The time of planting- if you have planted your potatoes early in the year before the ground temperatures are above 45F you will be waiting longer for the crop to grow than if you planted in Mid-April when the temperatures are much higher and the seed is going into warmed soil.

Also if the crop is going into a well-fertilized field it may grow for longer than if it went into a poorer-fertilized field but this is not what you should want.

You should plant your crop in relation to when you want it. For example, if you want early potatoes you should get them planted early in the year (February – March) and if you want maincrop you should plant them in (April – May)

How late can you plant potatoes?

I would advise against planting potatoes later than the start of July. Planting this late could take your growing season into November. Harvesting in November may not be a good idea as it will be colder and wetter depending on where you live. The cold, wet, weather may lead to problems getting the crop to bulk out, or become waterlogged or frozen before being harvested.

Can you grow potatoes all year round?

In some milder climates potatoes can be planted in the fall and harvested in the spring, but I would start by getting used to growing potatoes at normal times of the year first before trying this, as growing potatoes can be high maintenance and involve a lot of supervision. Once you get the hang of it you will be aware of the various ups and downs associated with growing this great vegetable and you will feel more confident about trying new methods and timings.

When to harvest new potatoes

New potatoes or Early potatoes are usually harvested in June or July these will have been planted in February or March and Maincrop potatoes are usually ready in September which will have been planted in April- May. You can get an idea of when to harvest potatoes when you see the flowers appearing on the plants.

When will the potatoes be ready?

It is usually 2 to 3 weeks after these flowers leave the plant for early varieties before they begin to be ready. Although they will be big enough they will have very thin skin and may taste “watery”.

It is better to let the crop mature and get good skin on the potato, by this time the potatoes will be cracking in their skin and be much more flowery or dry to eat and be much more flavourful.

The same goes for maincrop potatoes -it is a little longer to reach maturity but if you let them mature longer you will have much tastier potatoes. The other thing to remember is that you should let the potatoes get a good skin on them if you are intending to harvest them for storage.

Avoid harvesting for storage in summer

When your potatoes are ready to eat you usually want to harvest them all immediately as you are excited. This is a bad idea as the potatoes may rot in storage as they haven’t fully matured and got their thick skin yet.

It is better to dig what you need for your dinner and leave the remainder in the ground to mature. In the summertime, it is too hot to dig potatoes for storage.

It would be much better to let the potatoes stay in the ground until the autumn and the weather gets cooler and the potatoes have matured. Now is a good time to harvest your crop before the bad weather comes and the frost ruins your potatoes.

How to harvest potatoes

When the weather has cooled in the autumn – usually by Halloween we try to get all the potatoes out of the ground before any hard frost comes and ruins our crop.

Try to pick a good dry day to harvest your potatoes so they are coming out of the ground dry. You don’t want to be digging your potatoes out of the soil dry and the rain coming on and soaking your potatoes and bags, as they will rot when you put them into the shed for storage.

Start at the end of the drill or bed and dig your garden fork in deep 3 to 4 inches away from where you think the potatoes are growing and then lift the full fork full of potatoes and soil out of the ground and tip it upside down on the soil.

This should break up the lump of soil with all the potatoes in it to make it easier for you to see where all the potatoes are.

Then gather them into a hessian sack or a wooden box keeping as much soil out as possible.

Next, pull your fork through the soil you have just dug to check if you have missed any and then take another fork full and turn it upside down and repeat the process.

The knack for digging the potatoes without damaging any is to keep your fork well back and to go deep.

Get below the level of the potatoes and then give it a good spread over the previously dug part you have just gathered. By the time you have a few bags dug you’ll be ready for your dinner!