How to Grow Potatoes in a Bag – 4 Easy Steps

Potatoes are one of the most popular vegetables grown in the UK, and for a good reason. They are versatile, nutritious, and easy to grow. But, growing potatoes in the ground can be challenging, especially for gardeners with limited space or poor soil quality. That’s where growing potatoes in a bag comes in.

Growing potatoes in a bag is a simple and effective way to grow potatoes in the UK. It requires minimal space and allows you to grow potatoes even if you don’t have a garden. In this post, we will take you through the step-by-step process of growing potatoes in a bag.

How to Grow Potatoes in a Bag: A Simple And Effective Method

What Do You Need to Start

To get started with growing your potatoes in a bag, you will need the following: –

  1. Seed potatoes
  2. Compost
  3. Fertiliser
  4. And a Suitable Bag (40-50 litres)

Step 1. How to Grow Potatoes in a Bag – (Seed Potatoes)

Firstly, potatoes have a wide range of planting times from February through to May,  as well as maturities (first earlies, second earlies, early maincrop and maincrop), as culinary uses like boiling, salads, roast, jacket, chips, mash etc. certainly all quite confusing for the novice.

What is a Seed Potato?

A seed potato is a potato that has been grown to be replanted to produce a potato crop in the simplest terms, they are potatoes that were grown to be replanted. 

What Seed Potatoes to Use?

There have been several tests made by various bodies providing results on which are the best ‘cultivars,’ (selective plant varieties) when you want to grow potatoes in a bag. One by the RHS (Royal Horticultural Society) found that some of the strongest ‘cultivar’ producers in 40L bags were:

  • Casablanca (First Early) – White-skinned, good for boiling, baking, and chipping.
  • Golden Nugget (Maincrop) – White-skinned, good for roasting.
  • Sharpe’s Express (First Early) – White-skinned, good for salad, boiling and roasting.
  • Maris Bard (First Early) – White skinned, good for frying, salads and boiling.
  • Lady Christi (First Early) – Yellowish-skinned, good for boiling, steaming, and sautéing.

Where to Buy Seed Potatoes?

You can try your local nurseries for the varieties above or other varieties of your own choosing if you want to buy your seed potatoes locally. However, to be sure you get the ‘variety’ you want your best option would be to buy online. There are several places like Jamieson Brothers Annan or Seed Potatoes Direct for example where you can purchase good seed potatoes sent directly to your front door.

Before You Plant

Prior to planting and growing your potatoes in a bag, all ‘varieties’ of potatoes will benefit from what is called ‘chitting’. To ‘chit’ a seed potato simply means to break the dormancy and encourage shoots to form prior to planting.

Why do we Chit Potatoes?

The reason for ‘chitting’ early and second early seed potatoes is to give them a head start over those that are not chitted.  When ‘chitted’ potatoes are planted, it helps them to establish more readily, leading to stronger and bigger crops.

Seed potatoes that are not ‘chitted’ will of course grow whether they are chitted or not, irrespective of them being first or second earlies or even main crop, so don’t worry if you haven’t carried chitting out on your own seed potatoes.

How to Grow Potatoes in a Bag - 4 Easy Steps (chitted Potatoes in an egg box)

‘Chitting’ May Benefit Potato Growth

How to Chit Potatoes

On each seed potato, look for a rounded end with ‘eyes’, or growing points where shoots will sprout from. Then to chit your potatoes, simply place the tubers ‘eyes up’ in an old egg box or similar container, in a light, frost-free room a north-facing window sill is a good place.

The seed potatoes will start developing shoots within a couple of weeks – when they have reached around 2.5cm in length, they are ready for planting.

Chitting should be carried out in late January for the ‘first early’ potatoes and mid-February for the second earlies. There seems little point, however, in chitting maincrop seed potatoes, simply because they have a much longer growing season, and therefore ‘chitting’ has no real advantage.

When to Plant Your Potatoes in a Bag?

To keep it simple, we look at 3 main types of potatoes. These types are based on when you plant your potatoes and then harvest them.

First Earlies – (also called new potatoes) 10 – 12 weeks to mature.

  • Plant in March (may need frost protection) and harvest in June

Second Earlies – (also called new potatoes) 14-16 weeks to mature

  • Plant in March (may need frost protection) and harvest in June

Maincrop – 16- 22 weeks to mature

  • Plant Mid to late April harvest late July to Sept
Calendar circling a date - Planting Seed Potatoes

Plant Your Seed Potatoes in March/Early April

Step 2. How to Grow Potatoes in a Bag – (Bag & Compost)

Good multi-purpose compost is all you need to start the growing process; this can be brought from any good nursery or you can buy multi-purpose compost online through Amazon.

It is advisable at this time to purchase a slow-release fertiliser as this will assist yields. This can be purchased at the same nursery where you buy your compost or alternatively, you can buy potato fertiliser online through Amazon as well.

How to Grow Potatoes in a Bag – What Bag do I Need?

Ideally, you will be looking for a bag size of around 40L. There are many ‘purpose-made’ bags on the market that are suitable for growing vegetables all types of vegetables in a bag.

Special vegetable grow bags should be able to be purchased along with your compost and fertilizer at your local nursery or you can also purchase potato grow bags online through Amazon.

The most important thing in a good grow bag is ‘sturdiness’ (so a bin liner is out of the question) and they should be able to drain well.

Many seasoned gardeners use old ‘punctured’ (for drainage) compost bags to grow potatoes. The choice is yours, perhaps if you are just starting out, propriety bags may well be a better option until you are more confident.

Step 3. How to Grow Potatoes in a Bag – (Planting)

Once you have your chitted seed potatoes, bag, compost, and fertilizer we are ready to plant.

Open the bag and fill it to about 1/3 full of your multi-purpose compost. At this stage, you can also work on your fertiliser to boost the yield.

Evenly place 3 – 5 of your chitted potatoes on top of the compost with the shoots facing upwards. Then cover them with about 15cm of additional compost and water well.

Remember, your bag/s should then be placed in full sun. If frost threatens then make sure you bring your bags in under cover and or protect the shoots from damage.

3 Planted seed potatoes in a bag

Evenly Place ‘Chitted’ Potatoes

Earthing Up

Potatoes are not frost-hardy. Therefore, as the plants grow, gently cover the green shoots (Haulms) halfway up the stems with more compost (Earthing Up) until eventually, the level is just below the top of the bag. 

This encourages tubers to grow and prevents the ‘tubers’ from turning green from exposure to light, and therefore being inedible.  Also, by earthing up it will assist with minimising potential frost damage. If you did not use a fertiliser at the planting stage, you can use a ‘balanced’ liquid feed every couple of weeks during the growing season.

Always remember to keep the compost moist but not saturated do not allow the compost to dry out. Occasional heavy watering is better than regular light watering as the water needs to get down to the lower roots. Be especially vigilant through times of drought.

Step 4. How to Grow Potatoes in a Bag – (Harvesting)

By early summer you should be able to start harvesting the early potato varieties. Check your potatoes once the plants are flowering, this is a sign the crop is ready. Also, one of the best guides to know when your early potato varieties are ready for harvesting is to know the number of weeks since ‘planting’ time.

This period should be stated when you buy your seed potatoes from your nursery or merchant, so remember to ask when purchasing them. Of course, you can always ‘dig down’ and look to see if they are ready, for maincrop varieties it is advisable to wait until your foliage turns yellow.

Generally, though a potato harvest

  • Depends on the date of the planting
  • Variety
  • Weather conditions throughout the season

When the potatoes are ready in your bag and before emptying, cut back all the potato foliage to make harvesting easier and perhaps lay a plastic sheet on the floor to keep things nice and tidy.

Then simply tip out the contents of your potato bag/s onto the sheet, so you can pick through the contents and get all those flavoursome homegrown potatoes.

First Earlies – These are good to eat when freshly harvested in  June-July in small amounts.

Second Earlies – Same as first earlies, small quantities eaten fresh in late June-July.

Maincrop – Empty your bags from September onwards normally. When storing, ensure the tubers are thoroughly dried, and stored in a breathable sack, in a cool, dark dry place with some air circulation. This will allow you to keep and store your potatoes longer than the early varieties.

Pest Control

How to Save Your Potato Crop if You Get Blight

There are a few diseases to watch out for when growing potatoes, however, Potato Blight can be and is a major problem from July onwards with later yielding crops.

Potato blight is an airborne fungus-type disease which attacks the foliage (and later the tubers) causing it to collapse. It commonly occurs in wet, mild, and humid conditions and is difficult to manage.

It starts with brown marks on the leaves, image left and quickly spreads so that all the foliage turns brown or black collapses and the plant looks patently sick; it cannot be missed.  Once it takes hold, there is not much that can be done as it spreads rapidly.

If this is a problem in your area maybe you concentrate on early varieties of potatoes in your grow bags and look at the possibility of blight-resistant seed potatoes (ask your supplier).


How Many Potatoes Can I Expect to Harvest From One Bag?

You can expect to harvest between 2-4kg of potatoes from one bag, depending on the size of the container and the variety of potatoes you’re growing.

How Many Seed Potatoes Do You Put in a Growbag?

The number of potatoes you can put in a bag to grow depends on the size of the bag and the desired spacing between the potatoes.

A typical potato grow bag that is around 40 litres in size can hold around 3-5 seed potatoes. It is important to make sure that each potato has enough space to grow and develop roots without competing with each other.

What is the best mix for growing potatoes in bags?

The best mix for growing potatoes in bags is a loose, well-draining, nutrient-rich soil mix that provides good aeration and water retention. A good mix for potato grow bags can be made by combining equal parts of peat moss, compost, and perlite or vermiculite.

You can also add in some organic fertiliser or slow-release fertiliser to provide additional nutrients for your potato plants. It’s important to avoid using garden soil or heavy clay soil in your potato grow bags as these can become compacted and restrict root growth.


There is nothing more satisfying than growing and eating your own homegrown vegetables, and potatoes are one of the easiest vegetables to grow at home in a bag without the need for a large garden.

Take your time, follow this step-by-step guide on ‘How to Grow Potatoes in a Bag’ and we are sure you will be enjoying your own home-grown potatoes soon.