Growing Grapes in Containers - Proof of Concept

I have been trying to grow dessert grapes in containers in a polytunnel in Ireland. This is an unusual way to grow grapes, and is quite different from the vegetables that I normally focus on within this Red Gardens project, but it is something that I've wanted to try for a while. We don't have a good climate here in Ireland for growing grapes outside, and I didn't want to devote valuable polytunnel space for growing these very vigorous plants. But years ago I came across a method used by a more experienced grower in a similar climate to grow grapes in containers. And after the second season of managing grape plants using this method, it has been an interesting example of thinking I understood something in theory, but taking a while to actually understand it in practice. And I think this season it has been successful enough that it could be a worthwhile method for growing grapes, in a climate that is normally too cool for these types of plants. I first read about this method of growing grapes in containers in a book written by Bob Flowerdew, a well-known grower based in England. I read it years ago, and although I don't have the book anymore, I thought I remembered the instructions for the fairly simple method that he used. Plant one grape plant in a large plastic bucket with holes in the bottom, filled with good quality growing medium. Hard prune it to a stump, and keep it outside over winter, so that the frost and the harsh winter weather can kill off any diseases or pests. Top up the container with compost, and bring it into the polytunnel or greenhouse in the early spring, where the warmer microclimate will encourage fast growth and an earlier and better crop of grapes. Leave a few of the canes to grow up a support, and prune the leaders when they get to the top, and regularly prune these plants throughout the summer to prevent them from getting too big. Water often, and feed these plants regularly, but there should be 4 to 6 bunches of dessert grapes produced on each plant, which sounded like a great yield to me, if I could get it. After the grapes are harvested in the autumn, move the plants outside, and over the winter cut back all the growth to leave just a stump again. Or at least this is what I remembered from that book, and they seemed like fairly simple instructions. But as with many written instructions, it's hard to understand what to do in reality, especially with the pruning, as so much depends on the details, and an understanding of how the plants actually grow. I think these are the type of instructions that make a lot of sense once you know what to do, but I don't have a lot of experience with pruning perennial plants like this. In January last year I bought 1 year old grape plants in pots, one plant each of 4 varieties that were available from a supplier, who seemed to have a sense of what varieties will do well here in Ireland. There are not a lot of options around here, as it's not a great climate for this kind of heat loving plant, and they seemed expensive, but I figured I would start with these 4 dessert or dual purpose varieties. I'm not really interested in growing wine grapes, as it's possible to buy a good quality grapes for eating. I planted each plant in a large grow bag, that can hold about 40 litres of growing medium. This is bigger than the 25 litre buckets that Bob Flowerdew seems to use, so there's more room for the roots, but these bags will be heavier, and without a handle they will be harder to move around. I filled the grow bags with a lightweight and soilless mixture of bagged growing medium, my own compost, perlite and vermiculite, and different forms of concentrated fertility, including seaweed for trace elements. I let these grape plants grow just inside the polytunnel doors for the summer, not expecting much for their second season. They became quite sprawling plants, taking up a lot of space, and I pruned them back quite a bit a few times. I did notice a few small clusters of grapes on these plants, but the birds and the wasps ate everything that developed. Last winter I did the first proper pruning of these plants, cutting back all the growth of the previous year, and leaving a main stem or trunk about 1 meter tall, as I was hesitant to cut it too short. Later in the spring, when the plants were growing in the polytunnel, I removed some of the new growth to leave 5 or 6 strong canes, and I realized that the trunks were probably too tall. If a cane sprouted from the top of this tall trunk, it would not have a lot of space to grow before it reached the top of the support or polytunnel space. It seems obvious now, that it is better for the canes to sprout from closer to the base of the plant, as it will give more space for them to grow, but this was one of those things that only made sense to me once I understood better how the plants grow. And I've come across this quite often with different types of plants in the gardens, where I need to see a plant growing in really good conditions before I can get a sense on how to actually look after it. For this year's pruning, I am cutting back all of the new growth from these 3 year old plants, and reducing the height of the older trunk quite a bit. Apparently the canes next year will sprout from the remains of last year's canes, so I am making sure to leave a few possible grow buds when I prune them. I need to make sure that there is enough spurs and buds on the shorter trunk for next year's growth, but also want the base of the plant to be quite low, so that there is more space for the canes to grow into. I don't think it's a really critical issue, but it will probably take a few seasons before I get a better sense on how much of the plant to leave when I prune it each winter. When selecting the 5 or 6 canes to continue to grow on the plants last spring, I made sure that there was one strong cluster of flowers developing on each of them, and removed any other clusters that grew. I wound these canes up with bamboo support, tied them on occasionally to keep them in place, and pinched off the leader when it reached the top of the space. Throughout the rest of the summer I regularly pinched off all of the new side shoots, to prevent the plants from getting too big, and hopefully encouraging the plants to focus on developing the existing fruit rather than producing more growth. There seemed to be a lot of these side shoots, and I don't know if this is normal for these varieties, or I was possibly feeding these plants too much. On some of the plants the fruit clusters seemed quite small, but on others they seemed too big, and I cut back some of the larger clusters to reduce the number of grapes. I had this intuition that there was too much fruit for the size of the plant, or the number of leaves that were on the plant, and that fewer fruit would probably grow larger and possibly sweeter. But again I'm not really sure about that, and I probably should have just let them grow to see how each of these varieties developed over the full season. I liquid fed these vines a fair amount, though perhaps too much. There were some leaves that were showing signs of disease, or some forms of deficiencies, which I removed whenever I saw them, but overall the plant seemed healthy enough, at least to my untrained eye. As with all types of container growing, watering was a really regular task, which I added to my morning routine, but it's something that I will definitely be automating next year. This watering only took a couple of minutes every day, but a dripper system set up on a timer could save quite a bit of time over the full growing season, and it would be one less thing to remember to do every day. The biggest issue with these plants came when the fruit started ripening in the clusters. Some of the grapes on two of the varieties rotted, likely from a fungal infection, with one variety starting quite early. I removed some of the lower leaves on the plants to let the sun in to warm the fruit clusters, and to improve the air circulation, but in the warm and calm air of the polytunnel I'm not sure how useful this was. This rotting definitely reduced the yield of these two varieties, and is something I would want to figure out how to avoid next year. The blackbirds were very attracted to the fruit of another variety, and I ended up wrapping a netting around all of the plants to prevent the birds from getting all of the grapes. So in the end the harvest of grapes was less than anticipated, but there was still a reasonable amount to eat, and it was great to be able to sample the four different types of grapes, though I'm not sure I like eating them all. I need more experience to know when to harvest the grapes so that they are at their best, especially with the four different varieties maturing at different times. I think I missed out on the ideal harvest time for two of the varieties, as I had to go away from the gardens for a few weeks in September. I harvested all the remaining grapes before I left, to prevent them from rotting on the vine, and I moved the plants outside of the polytunnel so that they could be watered by the rain. In the end my neighbours probably got to eat the best of these varieties, so I'll have to wait until next year to properly evaluate the taste of all of them. I'm currently doing the winter pruning, and I will be saving quite a few of the vine cuttings to propagate new plants of these four varieties. I haven't done much hardwood propagation like this before, but it seems simple enough, and a lot cheaper than buying in one year old vines from somewhere else. I'm still not sure if I want to continue to grow all of these varieties, or how much space I want to give over to a fruit and crop like this. But because it takes a few years before the vines will really produce, I like the idea of propagating a bunch of plants now so that I have them when I figure out what I want to do with them. But I need to accept that I will likely end up abandoning a lot of these plants, rather than trying to find places to grow everything that I propagate. I've also been in touch with another grower and supplier who has other varieties available, either as one year old bare root plants or as hardwood cuttings. I'm really tempted to try out a lot of different varieties of eating or dessert grapes, to see which ones grow well with this method, in these polytunnels, and to find the ones that we really like to eat. So I expect I will have quite a few large grow bags of grape vines to look after in the next few years, and I'm going to have to figure out where they will all grow. Grapes were another crop that I really wanted to grow, but thought would be too difficult to grow here in Ireland, or to incorporate into busy vegetable gardens. But now I know that I can grow grapes in containers like this, that it is a viable method, even with the rot and the birds getting a lot of the grapes. It just depends on how much space within the polytunnels, and how much time and other resources I want to put into this crop, and how many grapes I want to get, but that is the same with all of the crops that I grow. This has been a proof of concept, for me at least, as somebody with a lot more experience than me has already shown that it could be done. I am only just beginning, but I already feel fairly comfortable with growing grapes like this. I now have a good sense of how much space the plants will take up when growing like this, what type of care they will need, when things will happen, some of the issues that may arise, and roughly how much I can expect from each plant. No doubt I will continue to tweak the method to suit my context, and the resources that I have available, to make the more repetitive tasks easier, and to hopefully prevent the pest and disease issues, and to deal with any new issues that do arise. I hope to get a better crop next year that is easier to manage, to learn more about these four varieties, and to try out new ones. And to continue to share my experiences and successes with others, just as Bob did for me. I think this is a good example of where learning from YouTube and other video based platforms can be really valuable, where they can offer a lot of visual information to back up the verbal or written instructions if they are done well. I think this is especially true for people who don't have the base knowledge or experience that would help so much if it makes sense. This is one of the reasons why I continue to make videos about growing food, as I feel that the visual information along with the verbal explanation can really help. If you like these types of videos, and value the kind of explorations that I do, please consider supporting my work through Patreon or PayPal. The links to both are in the video description below. I want to thank all those people who have supported this channel over the years as they've helped to keep it going, but more importantly, thank you for watching.