Do not let the size of your garden hinder you when it comes to planting and growing potatoes and other vegetables. In this post we will find out the 4 easy steps as we explain ‘how to grow potatoes in a bag’.
This growing potatoes in a bag can be undertaken in any small garden, backyard, patio, or balcony so everyone who has an interest can try it out.
Growing potatoes in a bag saves space and reduces the risk of disease, these couple of important points alone offer the novice gardener and professional alike a greater chance of success.
How to Grow Potatoes in a Bag - (Video)
What do You Need to Start
To get started with growing your potatoes in a bag, you will need the following: –
- Seed potatoes
- 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), also 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 are wanting 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 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 ‘first early’ potatoes and mid-February for 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, then harvest them.
First Earlies – (also called new potatoes) 10 – 12 weeks to mature.
- Plant in March (may need frost protection) harvest in June
Second Earlies – (also called new potatoes) 14-16 weeks to mature
- Plant in March (may need frost protection) harvest in June
Maincrop – 16- 22 weeks to mature
- Plant Mid to late April harvest late July to Sept
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 the 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.
How to Grow Potatoes in a Bag – What Bag do I Need?
Ideally you will be looking for a bag size 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 things in a good grow bag are ‘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 in your fertiliser to boost the yield.
Evenly place 3 – 5 of your chitted potatoes on top 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.
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 prevent the ‘tubers’ 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 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 earlier 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 date of planting
- 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 – 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.
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 It is an air bourne 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 a hold, there is not much that can be done as it spreads rapidly.
If this is a problem in your area it 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)
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.