If you haven't experience the almost child-like joy of digging for potato treasure because you live in a small space or apartment, then growing taters in containers is for YOU! I’ll run through what works for me on my Balcony.
Firstly, as with any growing in your small space, check your grow zone to know when the right time to get the spuds into the ground is. You can read my blog, Know Your Balcony Growing Zone which is a great place to start. The timing for planting potatoes in containers is similar to that when planting into the ground. If you're in a frost-prone area and receive frost in your small space, you will want to plant them before the last expected frost, and you can continue through into Summer.
The safest and best quality potatoes are grown from "seeds" that are not seeds but tubers that are potatoes. Some pundits use potatoes from the greengrocer, and often these are sprayed to stop sprouting (a bit unsightly on a store shelf) and may harbour diseases. Purchase your certified Seed Potatoes from online and garden stores.
It is possible to grow potatoes from large pots to my favourite Root Pouch grow bags in any large container! Root Pouch fabric grow bags are lightweight, environmentally friendly, and made of spun recycled BPA free plastic, so they are 100% food-safe, and the Potatoes get air as they grow. Make sure that whatever container you use has excellent drainage. With a Root Pouch bag, the Potatoes will never sit in water and rot.
Potatoes will grow well in a range of different sized containers. For Root Pouch grow bag growing, consider the #22 (22L) grow bag to grow 2-3 seed potatoes through to the #76 (76 Litre) grow bags to plant 4-6 seed potatoes and through to our garden bed sizes. As a rough guide, each potato plant needs about 10 litres of soil. Overplanting a container will lead to small or deformed fruit. Plants will struggle to thrive and may even fail to produce a crop. Find out more about the range of Root Pouch grow bags HERE
Know the difference between indeterminate and determinate potatoes!
Determinate potatoes are varieties with tubers that grow in just one layer. For this reason, the plants do not require mounding of the soil around them. They produce early, in about 70 to 90 days. Indeterminate potatoes grow in multiple layers, so it is important to mound soil around the plants. This will give you a better yield. Indeterminate potatoes produce late crops, 110 to 135 days out.
This planting guide will focus on the planting of Indeterminate potatoes using the rolled grow bag method.
Some folk wait for the taters to sprout shoots before planting them whole; others plant the seed potatoes immediately. What I like to do is, if the potatoes seeds are large, I cut whole seed potatoes into pieces a little larger than a large egg, each with one or two "eye" buds on them. Then, I place them into a supportive container such as an egg box and keep them in a light but relatively cool place to produce stubby, dark green shoots.
A high-quality potting mix that is rich and free draining is acceptable for growing medium for potatoes in bags. However, potato plants need nitrogen and potassium in the soil to set tubers and produce enough carbohydrates for the tubers to grow into sizable potatoes. Compost has been known to be better than potting mix.
If you are mixing your own, a good mix is 1/3 good quality finished compost, 1/3 vermiculite or perlite, and 1/3 coconut coir or peat moss.
You can also add a couple of handfuls of organic fertilisers, such as chicken manure pellets, for good measure.
I'm focussing now on using the hilling method in a grow bag. If you're using a rigid container, follow the same principle of layering the soil and leaves.
Planting Indeterminate Potatoes:
Fold or roll the sides of the bag down till it is about half the height; you will unroll/fold this as you build the soil up around the leafy tops. Fill the bag with at least 10cm of mix or compost and set the seed potatoes in the potting soil. Place the seed potatoes evenly in the container. Cover the potatoes with a layer of soil to fully cover the potatoes and water well.
Once your potato plants have grown about 10cm, you need to "hill" them. This is done by adding about 5cm of potting mix, compost or something like pea straw around your potato plants, covering the growing stems at the bottom. Be careful not to break the plants in the process. The goal is to bury about one-third of the plant, covering the lower leaves with soil. The buried stems will produce more potatoes, so this hilling procedure is essential to a good harvest.
You will need to repeat this hilling process by rolling open your bag a few more times as your plants grow. You can also stop once the soil reaches the top of your container.
If planting determinate potatoes, bury the potatoes seeds and cover with soil and feed them throughout the growing season. The Olla should be used when growing a determinate variety of Potatoes as no hilling is required. Bury it to its shoulders in the middle of the bag and surround it with the determinate variety of potatoes.
If you are using the Grow Potatoes Pack, the Olla is most effective when growing determinant varieties of potatoes as hilling is not required. Potatoes will not grow without sun and water. Overwatering will result in rotting tubers. Underwatering will result in lower potato yield. Remember that one of the keys to growing potatoes is keeping your soil moist, not wet. Potatoes do not like long hours of hot, direct sunlight day after day. If your space is scorching, you may want to partially shade your plants which is the beauty of grow bag growing potatoes!
Make sure your container receives at least six to eight hours of sun a day. If you have used a fresh potting mix, there will be sufficient nutrients in that mix to sustain the plants for the number of months stipulated on the potting mix bag. To care for the plants and support their growth, add a solid (powder, pellet) slow-release fertiliser at the start of spring when the plants start growing. To maximise productivity, add fertiliser every 6-8 weeks during the growing season. Liquid fertilisers should only be used as a top-up supplementary feed; they wash out easily and aren't long-acting.
Plants use the nutrient phosphorus for root formation, stem growth, and fruiting, so it's particularly important to all root crops, including potatoes. Therefore, it's best to use a balanced fertiliser that will typically contain ample phosphorus and provide all necessary nutrients in the right amounts.
Fertilisers such as chicken manure or blood & bone are particularly phosphorus-rich and are great for use around root crops.
Potatoes are usually ready to harvest in 15-20 weeks or 4-5 months after they're planted. Depending on the timing, potatoes can be harvested early while the plant is still growing in January; or wait until Summer ends, and Autumn nears when the potato leaves and stems begin to turn yellow. You can also start to harvest potatoes any time after the plants have flowered. When the foliage has died back and cooler weather sets in, stop watering about two weeks before harvest.
Reach down into the soil of your container and pull out a few new potatoes at a time. Then, as the plants turn yellow and die back late in the season, you can harvest all the remaining potatoes at once. The easiest way to do this is to turn the grow bag or container out.
Enjoy being an Urban Potato farmer!
Our customer Rose C. of NSW has grown a bed of Potatoes using a Root Pouch garden bed
Do you want to enjoy your holiday away from your precious pots and not worry about how your garden is doing while you're away? It can be difficult to leave your garden for a holiday or work travel. This is especially true if you have a vegetable garden. A little preparation ahead of departure day will give your small space garden the very best chance of surviving without you! Plants in pots tend to dry out quickly.