When we got them we planted our first three strawberries all in one pot - a large fish box - and last year I realised that it wasn't a very good idea. While the plants grew strongly and did produce strawberries it was very hard to look after them as there was such a massive tangle on leaves. There was too much cover for slugs and woodlice to hide. The leaves of each plant overlapped each other creting a dense thicket. These guys obviously aren't the best friends of strawberries and so conditions that are unsuitable for them are to be encouraged.
The plants are in their dormant stage in this photo so there are only about 25% of the leaves that were present during the summer.
Also, the fact that there were so many leaves all overlapping each other meant that most of the strawberries were trying to ripen in very damp conditions. As a result of this a good few went mouldy (botritis) before being ready to eat :( Only the ones that hung over the edge and were able to escape the sprawl were salvaged.
Here is one that was planted in a pot by itself and this fared much better. We have about 7 of these and overall I think that if you are keeping strawberries in pots then they should be potted up singly. It was easy to see the growing strawberries and check for any slug damage. Also it was easier to look under the pots to see where the feckers were hiding as the pot was smaller and lighter.
Originally I had decided to repot the three in the fishbox but then I thought of a better idea. These three big healthy plants are going to be this year's Mammys. In order to get really good runners I have read that you should dedicate a plant or two to this purpose alone and prevent them from fruiting. All the energy then goes into the runners and so next year's plants get a good start.
Even though I have enough strawberry plants in the garden it is still important to keep propagating new ones. There are two reasons for this 1) Strawberry plants start to loose their vigour after 3 or 4 years and so they should be replaced with new ones in order to ensure good crops. Rather than replace all your plants suddenly you should propagate enough every year to replace about a third so that you have a steady supply of mature plants.
As you can see the crown on this guy is quite large and so I think it will do a good job. But just to make sure I added some manure as a top dressing. I wouldn't normally add manure to the strawberries this close to summer as it's not too hygenic for the strawberries to be sitting on them. But as these guys will not be making fruits it should be fine.
The manure will go towards making nice big foliage which should strengthen the plant overall.
Here is the manure in place. I put in about two inches of it so we'll see what happens. When I start to see any little flowers emerging I'll pick them off and just allow about 5 runners to develop per plant. I'll probably cut off any weak ones and allow the strong ones to mature.
To find out more about runners and how to get them to root and all that have a read of this post