Strawberries, Choosing & Planting Up Hanging Baskets

For the past 6 years I’ve been growing my strawberries in hanging baskets in the polytunnel. The system works really well for me and whilst it is not problem free, it works better than growing outside.

Strawberries planted in hanging baskets in polytunnel.

The biggest benefit to growing the strawberries in hanging baskets is that they don’t get slugs and snails going for them. Usually, they’re safe from birds too, although one enterprising winged miscreant caused problems. Until the sleeping cat awoke and scared him off.

The strawberries also benefit from the extra warmth in the tunnel and they are sheltered from heavy rains.

The space used would likely not be utilised at all, so it’s ‘free space’ On top of that, I get 6 plants per 40 cm diameter basket, giving a planting density some 10 times higher than planting in the ground.

Baskets versus Strawberry Barrel

I’ve tried a strawberry barrel in the tunnel, which gives the highest number of plants per area, but it’s vulnerable to pests and the individual plants don’t do as well as they do in the hanging basket system.

Problems Growing Strawberries in Hanging Baskets in a Polytunnel

But the system isn’t without problems. The baskets can dry out easily in hot weather, so they need more attention. Keeping the plants fed can be a problem as well. Another problem is that polytunnels can be quite humid, which encourages moulds.
Finally, strawberries need to be pollinated to produce fruit. Outside, this is done by insects – flies and bees being the main pollinators. In an enclosed space, like a greenhouse, you can hand pollinate, but it’s time-consuming.

Remedies to the Problems

To stop the baskets drying out, I add water retaining gel to the growing medium. For feeding, adding slow-release fertiliser in the original potting compost provides a base supply throughout the season. Then I feed as I would tomatoes. Nitrogen rich when initially growing to push leaf growth, and then potash rich when flowers appear.

With the polytunnel, I find it best to open the doors and get good ventilation whenever possible. This decreases humidity and mould problems whilst allowing pollinating insects access.

Renewing Stock

Strawberry plants don’t last forever, so a rolling renewal program is best for yield. I’ve plenty of replacements available grown from runners but wanted to try some new varieties.

I came across Moore Berries, who grow a decent range of strawberry plants and other soft fruits. After looking at their web site, decided to go for Vibrant and Symphony. They recommend Strawberry Vibrant for pots and hanging baskets, plus it’s got good resistance to mildew. Strawberry Symphony is developed to be tolerant of damp conditions and, again, are mildew resistant.

It’s worth asking an expert, and after growing strawberry plants commercially for 30 year, I reckon they count as experts. I emailed explaining my growing conditions and they agreed these were sensible choices for me.

In the past, I’ve bought bare-rooted strawberry plants via Ebay. Shall we say the quality is variable. Sometimes I’ve been very happy, other times disappointed. Moore Berries delivered high-quality plants, carefully packed and labelled in a box, along with an instruction sheet for beginners. The price from Moore Berries is on a par with most Ebay sellers.

Opening the box – strawberry plants arrived.

The first job on unpacking is to soak the plants in water for a couple of hours to rehydrate them. It does help if your bucket doesn’t have a hole in it, like mine. Try again with another bucket and much use of Anglo-Saxon expletives.

Note the superb root development on these strawberry plants

Potting Mix for Hanging Basket Strawberries.

As the plants soaked, I mixed up the growing medium and found out a couple of hanging baskets and liners. The mix I use for the hanging baskets is as follows:

• 4 parts multipurpose potting compost
• 1 part aeration mix made of 7 parts perlite and 3 parts coarse vermiculite
• Water retaining gel – about 40g per basket (40cm dia basket)
• Slow release fertiliser (Miracle-Gro Continuous Release All Purpose Plant Food) about 60g per basket

All parts by volume Mix thoroughly.

Planting Up Hanging Baskets

Planting second layer of strawberries in the hanging basket. Note the roots are spread out.

The hanging basket is placed on the bench and liner inserted. The liner has six segments and each segment has two planting slits, one low and one high.

Add the growing mix up to the level of the first slit. Then feed a plant, crown first, through alternate slits. You then have 3 plants spaced around the basket. Spread the roots out and recheck the crown is in the right position, with the head just slightly proud of the basket.

Add another layer of growing mix up to the level of the second, higher slit. Feed the next 3 plants through the slits using the segments that don’t have a plant in the lower slits, so alternating around the basket.
Again, spread the roots out and fill the basket to the top. Water well, top up the growing mix and leave for an hour. If the mix has sunk, top up and water again.

If you have a spare plant, you can put in the centre of the basket rather than waste it but aim for six per basket.