At the end of May I reported on a nightmare aphid infestation. Drastic preventative measures seem to have worked, so far...
I think 2019 is shaping up to be the Year of the Aphid. It seems like the sap-sucking pests are everywhere at the moment: all over the Aqualegias in the back garden, on the onion seedlings in the greenhouse and in a particular nasty manifestation, infesting one or two of the trees in the Plot #79 allotment orchard...
Comfrey tea, or comfrey fertiliser, is an all-organic, easy to make plant food that provides excellent nutrition, especially for flowering and fruiting plants.
When I make comfrey tea I use a method that was told to me by no-dig guru Charles Dowding and it goes something like this...
A couple of weeks ago I enjoyed the opportunity to work on a rather lovely Bramley’s Seedling tree that hadn’t been pruned for a while and was starting to get too big for its space.
The owner of the tree – which was highly productive last year – was very keen that it shouldn’t just be hacked back, but wanted to gain space around the base of the tree for lawn maintenance and accessing the border that the tree is planted.
The clear answer was a crown-lift: removing three large, low-growing branches to reduce crowding at the base and allow in more light as well.
Here’s a pic of the tree, with the three branches marked for removal:
Unfortunately, I forgot to take a pic the side to show just how much it leans out away from the fence: the fence and next door’s garage are to the south to south-west and so the sun is blocked for large parts of the day; the tree grows out into the middle of the garden as a result, looking for light.
The three marked branches plus one more around the back – and particularly that thick one – growing low and potentially dangerous to unprotected eyes, were following the same pattern. In addition, and even more importantly, they were adding a lot of weight to that side of the tree and contributing to the the lean of the trunk.
Here’s a close-up of the area I was working in:
And here’s how much cleaner and less congested it looks after the branches were removed:
I used good, sharp tools – bypassloppers to take back the branches and reduce the weight, then either a Felco F180 or SilkyFox Pocketboy pruning saw to finish – to make clean cuts that should heal nicely once the tree emerges from dormancy. I cut on a good, steep angle to ensure water would run off as well:
Looking at the rings on the cut end, I reckon that branch that been growing and thickening – adding to the weight on that side of the tree – for a good seven or eight years:
(RHS Level 3 revision, anyone..?)
Looking at the post-pruning shape of the tree, although the photo isn’t amazingly clear, you can hopefully get a sense of how much more open and balanced it looks:
Admittedly, there are still parts of the tree that need work: the crown is a little lofty and could perhaps be reduced, and that odd-angled branch on the right of the pic is another possible candidate for removal. But as I judged I’d already removed around 15%-20% of the tree’s canopy, I decided to stop there and not make any other cuts – aside from removing a few damaged or congested smaller branches from the centre of the tree – rather than risk causing too much imbalance in the tree this growing season.
I’m going to go back and take another look at it in the summer to see how the tree has responded to the cuts I’ve made and then I’m hopeful that I’ll be asked back next winter to work on it again: maybe a crown reduction or a more general thinning next time, once that problem branch has been addressed and corrected.
In the meantime, here’s hoping the owner will enjoy another year’s bounteous harvest. The tree is covered in potential fruit buds, so as long as the weather and the pollinators (the tree is less than half a mile from a 15-hive apiary, so that shouldn’t be a problem) are kind, then there should be plenty more apples to enjoy for many years to come:
A timely reminder from Monty on last week’s episode of Gardener’s World sent me down to the greenhouse yesterday afternoon to check on our stock of over-wintered Dahlia tubers.
Dahlias are perennial plants that over-winter by storing sugars in large tubers below ground. But these tubers aren’t particularly frost-hardy or water-proof, so they do require protection to get them through the wet British winter. So they were dug up, dried out and potted up in spent compost last November, just after the first frosts killed off the foliage.
They’ll soon (hopefully) be bursting into new growth, which makes now the ideal time to check them over and make sure they’ve survived their winter hibernation intact. Here’s how:
1. Quick Visual Check
Start by tipping the Dahlia tuber clusters out of their storage tubs, and have a look for any obviously rotten, shrivelled or split tubers. Remove those, either by very carefully cutting them away with a sharp knife, snipping with secateurs, or gently twisting the affected tuber, which carries less risk of accidentally damaging healthy tubers.
2. Manually Check Every Tuber
It’s important to check every singly tuber in the cluster, in case there’s one that looks fine but is actually rotten beneath its skin. Give every tuber a squeeze to make sure it’s firm and healthy, once again removing any of them that aren’t.
You’ll soon find out if a tuber is rotten. Luckily, squishy tubers don’t seem to smell all that bad, but there’s always a risk of squirtage, so don’t squeeze them too hard…
3. Clean Up and Re-Pot
Once you’ve cut, snipped or twisted off any dead or diseased material, you should be left with a clump of healthy tubers, attached to a section of stem. At this point, you can also divide large clusters of tubers. Sometimes they split and separate during the checking and cleaning process. Otherwise, a bit of gently pulling might reveal a faulty line that you can take advantage of.
As long as the section you break off includes one or more storage tubers and a section of the stem / growth node part of the plant, then you should be be able to pot it up and grow on a whole new Dahlia plant from it. We started off with five or six bought-in tubers and over the past couple of years have increased our stock to around two dozen plants.
Re-pot each tuber into a mixture of spent and fresh compost. You can use all-fresh compost, which isn’t a bad idea if you’re planning on keeping the Dahlias in pots year-round, but I’ve found found that if you’re planning on planting them out when all risk of frost has passed then a 50:50 mix of spent – you can re-use the over-wintering compost – and fresh is fine. Once the plants go into the ground they’ll be able to draw on the nutrients in the soil.
Hopefully your efforts will be rewarded with a glorious display of dazzling Dahlias from mid-summer right through to Autumn!
Here’s an item that allotmenteers might be interested in. Researchers at the University of Coventry, in partnership with the RHS, have published the results of a study into the damaging effects of bad digging practice, along with a few suggestions as to how to improve your posture and technique to help reduce the risk of back and shoulder damage.
Using the University’s 3-D motion capture technology lab, the team assessed the impact of various digging methods in terms of musculoskeletal damage risk. In the researchers’ words: “A novel method of determining joint angles, joint torques, and contact forces, using three-dimensional motion capture and musculoskeletal modeling, was applied to the movements of a sample of workers, engaged in the horticultural task of digging, to determine if objective biomechanical data could be correlated with a subjective visual assessment to predict risk of injury.”
The general conclusion – which was also mentioned in a short article on BBC Breakfast on Monday – is that good posture and practice involves standing as close to the spade as you can, bending with your knees rather than your back, and using smooth, regular actions (top row, below). Bad technique involves stretching and reaching with the spade, bending the back and using jerky, irregular actions (bottom row).
The full study has been published in the journal HortTechnology. One thing I noticed was that the 15 subjects that participated in the study were asked to use the same spade throughout. Which makes sense from the point of view of comparing two digging methods, of course, but it would have been interesting to see if there was any difference between the standard ‘digging spade’ used and a long-handled spade or shovel, which I’m a big fan of. The latter allows for a more upright posture, provides more leverage during the digging action, and seems to encourage more leg and shoulder work, rather than back-twisting, which the study highlights as a particular danger. But that’s just my experience, and a motion-capture study might prove me wrong.
Of course, if you really want to minimise the risk of musculoskeletal damage, you could adopt Charles Dowding‘s no-dig methods and save yourself a lot of back-ache that way.
This year we’re growing three Andean tuber crops down on Plot #59: Oca, Yacon and Ulluco. It could also be the last year that we grow the third of that trio. DEFRA – the government’s Department for Environment Food & Rural Affairs – have issued a biosecurity warning, because some Ulluco tubers imported into the UK may be infected with several non-native viruses.
The situation is a serious one: the viruses could potentially infect plants of three major families: Amaranthaceae (spinach, beets, chard etc.) Cucurbitaceae (squash, pumpkin, courgette, etc.) and Solanaceae (potatoes, tomatoes, etc.) so that’s a number of our major food crops. I double-check with the head gardener where I work – Lindsay Berry, M.Hort – and she confirmed that yes, this sort of warning should be taken very seriously indeed.
Frustratingly, DEFRA haven’t updated their website with their own biosecurity alert, so I can’t point you straight to the source, but Emma at the Unconventional Gardener blog has posted details of the warning, along with a copy of the DEFRA document that was issued to tuber suppliers and sent on to me by the folks at Incredible Vegetables, from whom we bought our tubers this year.
This is the relevant section of the DEFRA document, with instructions to Ulluco growers:
- Ulluco should only be harvested for personal consumption and should not be sold or transferred to other sites (and all tubers should be removed from the soil).
- Tubers of ulluco should not be saved for planting in the following year.
- If potatoes and species of Amaranthaceae, Cucurbitaceae and Solanaceae are also grown nearby to ulluco, these should only be harvested for personal consumption and any seed/tubers should not be saved for planting in the following year.
- Any remaining waste from the vegetables, including peelings, can be disposed of in general waste bins to go to landfill and should not be composted.
- Remaining plant material (leaves and stems) of ulluco, should be destroyed following harvest, either by incineration (burning on site), via deep burial (to a minimum of 2 m) or bagged and disposed of with waste for land fill.
- Remaining plant material or potato and species of Amaranthaceae, Cucurbitaceae and Solanaceae, which you have grown, should be destroyed following harvest, either by incineration (burning on site), via deep burial (to a minimum of 2 m) or bagged and disposed of with waste for land fill.
- The planting area should be cleared of all plant material, including weeds.
- If any ulluco and potato plants regrow in the following year, they should be destroyed as for the plant material above.
- The viruses are potentially transmitted mechanically (on people, clothes, equipment etc.), so hygiene best practice should be followed:
- Wash hands with soap before and after working on a crop.
- Clean any tools and equipment which have been in contact with ulluco thoroughly to remove all plant material and soil.
Once again, rather frustratingly, there’s no information on how to spot signs of a definite viral infection, or whether the viruses are likely to persist in the soil next season, which of course would prevent growing any crops from potentially infected species. Although, as DEFRA hasn’t told us to immediately destroy all Ulluco crops and remove the soil, it would seem that the viruses in question might need a living host to persist?
In any case, because of the potential risk for mechanical transmission, I spent an unpleasant couple of hours on Sunday dragging half-decomposed vegetable matter out of our large compost bay – to which for the past few weeks I’d been adding the foliage from this year’s squash plants, which had been growing right next to the Ulluco – then bagging it up and taking it to the municipal tip.
So that’s an entire year’s worth of compostable material destroyed, because DEFRA haven’t specified the precise conditions under which the viruses can persist. Still, better safe than sorry, eh? I’d rather loose a year’s compost than risk a future year or more’s potato, tomato, squash and beet harvest.
I just hope we have a decent Ulluco crop this year, to make up for all the hassle.
I’ve been growing leeks using the same method for the past three or four years now and it seems to be working quite nicely.
Rather than tray-sowing and then pricking out individual leeks into modules, I use deep plastic troughs – the sort of thing you can find in most large supermarkets at this time of year or online of course – about half filled with general purpose compost. On top of that I layer about 5cm of seed compost, and sow the leek seed thinly on top, before covering lightly with seed compost and watering with a fine-rose can.
A few weeks later, the leek seedlings should be about 15-20cm tall and looking rather grass-like. This is when I like to thin them out and give them a trim.
If there are two or more seedlings growing within about 1cm of each other, then one or more of them has to be plucked out. Be ruthless. Better to have one good seedling with enough room to grow to planting-out stage than two or three that eventually compete each other to the point of uselessness. Plus, the leek-trimmings can be used like chives, in pasta, fritatta or anything else you fancy.
Next, take a pair of sharp scissors and give your leeks a hair-cut. I gather up a small bunch and then chop the lot off at around 10-12cm in length. Trimming the main growing shoot(s) helps to prevent them becoming hopelessly leggy and tangled. It also encourages the growth of new leaves from the basal plate at the bottom of the leek, and that’s what you want: a thickening of each seedling to roughly ‘pencil thickness’, ready for planting out in June or early July.
If you’re thorough (and brave) enough then you might only have to thin your leek seedlings once before planting out, although a second trim may be needed in another three or four weeks.
How about you? Is this how you grow leeks, or do you use a different method? Let me know via the comments.
Successional growing – staggering the sowing and planting of crops – is a great way of to extending the harvest over a longer period and avoiding those “help, I’ve run out of chutney recipes” gluts.
It tends to work best either with fast-maturing crops like salad leaves or radishes which, with a bit of experience and also luck, can be sown every few weeks so that just as one batch has been harvested, the next ought to be ready to pick. But it doesn’t always work for slower-growing crops, which can often just sulk when the weather is poor and then put on a burst of growth and catch up when the weather improves. I’m thinking beans, courgettes, that sort of thing.
Another successional method, which does work well for slower-maturing crops, is to extend the season by over-wintering hardier varieties; sow and plant out in autumn, provide protection against winter frosts and/or rain, then watch them grow like the clappers as soon as spring rolls around.
Last year, we tried over-wintering a batch of broad beans. We planted out 20 ‘Aquadulce Claudia’ – a recommended hardy variety – under enviromesh, and only lost two to the winter weather. Here they are just a week or so ago:
They’ve already flowered and are setting beans, and we’ve been picking the leafy tops as a bonus veg crop as well.
We then sowed another batch – this time a mixture of ‘Aquadulce Claudia’, ‘The Sutton’, ‘Rd Epicure’ and a mangetout variety called ‘Stereo’ – and planted them out in mid-April. Here they are in a pic taken at the same time as the above:
They’re just about starting to flower but they’re a good few weeks behind the over-wintered batch. That should mean the beans are ripe much later, so we might have had a chance to eat all the over-wintered ones before the new ones are ready.
Other crops with cultivars that over-winter well, or that can be harvested in the winter months, include onions, cabbages, kale, leeks, peas, sprouting broccoli, brussels sprouts, parsnips, carrots and of course garlic. We always plant our garlic and elephant garlic cloves in September as a couple of sharp winter frosts will help the bulbs to form properly. The same goes for strawberries; the best time to plant them out is in the Autumn.
How about you? What have you over-wintered from last year and is it doing well? Let me know via the comments, below.
Compost, rich in organic matter, is one of the essential building blocks of good soil. It helps retain moisture and adds nutrients as well as binding mineral particles into a lovely crumb structure. It’s great to add to sandy soils to help them clump together, and clay soils to help them break down. Or any soil, for that matter, to improve its overall condition.
Making compost at home is incredibly easy. Not all of us have room for the sort of multi-bay composting setups that Monty Don or Charles Dowding have access to, but the good news is you don’t need a huge amount of space to run a really efficient composting system.
Having experimented over the past few years, I can highly recommend a rotation system using either two or three of the standard black compost bins. They’re available from most DIY stores and garden centres, but you should definitely check online with GetComposting.com to see if your local authority has a subsidy scheme that could get you a couple of standard bins at a very good price.
We have enough room in the utility corner behind our shed for a three-bin setup. The two bins on the right at the ‘current’ and ‘resting’ bins. The ‘current’ bin is the one we’re adding new material to at the moment. They’re open-bottomed, placed on bare soil (or in our case, sand) to allow worms and other organisms easy access to the contents. They’re technically ‘cold’ bins, as they’re not insulated to retain internal heat (like the pricier but more efficient HotBin composter), but they are sited in a spot that catches the sun (as you can see) so they do heat up pretty quickly on a warm day.
There’s a vast amount of information and advice available as to the right mix of nitrogen rich ‘green’ (living or recently-deceased plant matter) and carbon-rich ‘brown’ (long-dead plants, cardboard, paper that isn’t too glossy or heavily inked) material to add your your compost. The RHS advice page on composting suggests a 25% – 50% ratio of greens topped up with browns.
We add all our kitchen peelings, including eggshells, and garden clippings, but not perennial weed roots1 or potato tubers, as well as the contents of our shredder, ripped up egg-boxes and cardboard tubes, along with regular sluices of water. We aim for a 50/50 mix, but it probably skews towards green due to the large amounts of veg trimmings we produce, even though we’re just cooking for the two of us.
The ‘current’ bin is gradually filled over the course of a year. Then it becomes the ‘resting’ bin for the next year. Nothing new is added to the ‘resting’ bin, and the mix is checked monthly, to make sure it’s moist enough and to give it a good stir around with the garden fork to get plenty of air in.
The switch-over between the two happens any time between now and the end of April, whenever I can find the time to scoop out last year’s compost and bag it up until it’s ready to use on the garden. I started on the job yesterday, and this is the sort of thing I found at the bottom of the bin:
As you can see, everything has broken down quite nicely over the past 12 months, into a dark, crumbly, odour-less mix that will make a great soil improver. There are a few clumps of egg-shell that haven’t fully disintegrated yet, but they can be plucked out and dropped back into the newly-designated ‘resting’ bin before the lid goes on for 12 months.
I think there’s between 120 and 150 litres of compost in just the one bin. Whilst that might not represent a huge monetary saving over bought compost, it’s still the value of a couple of potted up perennials or a few packets of seeds. So in terms of the return on the cost of the initial investment in plastic bins, I’d reckon it will pay for itself in around three or four years.
The third, left-hand, bin is for woody waste: tougher plant stems, clumps of grass, anything that you know will take a longer time to break down. This bin will be left to do its thing for at least three years, allowing as much time as possible for the thicker plant material to break down. At the end of three years the contents will be scooped out and sieved. Any usable compost will be extracted and the rest of the material will go back in the bin for further decomposition.
The main advantage of running two bins side-by-side is that you can ensure a full breakdown of the contents of the ‘resting’ bin over the course of twelve months – especially if you switch at the start of Spring, to really get the temperature up over the summer – without the problem of having to add fresh new material on top of the compost you’re trying to extract from the bottom. That’s always a messy, smelly way to do things, not really recommended if you can avoid it. And you can manage perfectly well without the third bin, but you may have to spend a bit more time picking woody chunks out of your ‘resting’ bin at switch-over time.
Finally, a quick pro-tip re: tea-bags. It’s very tempting to assume that they’re entirely biodegradable, but experience – and much sieving – has taught me that’s not the case, as many tea-bags contain artificial fibres. I’d rather not spend extra time picking chunks of half-rotted bag out of the finished compost before it can be used, so instead I invest a smaller amount of time in splitting the tea-bags open and collecting the spent tea leaves before they go in the compost:
I dump them in the sink to rinse, then squeeze them out and leave them to dry in a dish on the side before ripping them open when they’re reasonably dry. It doesn’t take too long to do – you can always split a few while you’re waiting for the kettle to boil or your next cuppa to brew – and it’s a lot less fiddly than all that picking-out.
Either that or you could always drink more loose leaf tea, which always seems to taste better anyway.
What are your experiences with composting at home? Do you have any suggested improvements on the way we’re doing things? Please do let me know via the comments, below.