Firstly, thank you to anyone who mailed me last week to let me know you found our most recent article on plant feed for container growing useful. It is always great to hear from anyone out there, whatever you have to say to me, but especially satisfying when a topic we cover hits the spot. Please let me know if there is any other subject you would like me to cover, I am always happy to oblige, it is a lot easier than shooting blindly out into the void.
This week I thought we would have a quick look around my vegetable garden to see what's happening. We had such a cold start that I was getting jumpy, almost everything was struggling, but with the recent warmer weather has brought a reassuring flush of growth. After the look around, I will also cover what you can sow or plant in June, there are still plenty of options for harvests through the summer and autumn and even into next year.
Keep 'em coming! As you probably know by now, I grow most of my vegetables from seedlings sown indoors in trays or pots which are then either planted outside or in the polytunnel. There are many reasons why I prefer this method including more reliable germination and avoiding slugs but one, often overlooked, advantage is you get to plant out the strongest plants.
I am sure you have noticed that in any group of seedlings, whether sown direct in the soil or in trays, that some will be more vigourous than others. I always sow double the number of seeds I need so I have some spares but also so I can have the pick of the strongest seedlings. 9 times out of 10, the largest seedlings will go on to produce the best plants so the minimal effort of sowing a few extra can make a big difference later on.
I will include a list of options later but my advice is to keep up with producing seedlings to have fresh plants to fill the inevitable holes in your beds where things didn't go your way or you have harvested another crop.
Potting on The quality of bagged compost can vary wildly and never has this been more true than this year after huge demand for garden products in 2020 and early 2021. It would appear compost raw materials were in short supply as the quality of bagged products has been patchy at best. I would expect this trend to continue as peat is phased out without a good alternative being in place.
Being unsure of compost has made me change by sowing technique slightly where I sow in smaller modules and then pot on to a richer compost mix before planting out relatively large plants. The new Charles Dowding trays (above) are ideal for this with a 3cm module that gives about 3 weeks of growing before seedlings need to be potted on or planted out. Remember, if your beds aren't ready to receive a seedling plant, you are much better to pot on to a larger container rather than let plants get pot bound and hungry.
I use a multipurpose compost and mix in 2% blood fish and bone and a little seaweed meal and pot into individual 7cm pots (above, apologies for the overexposed thumb) or 5cm modular trays (further up). Blood, fish and bone is slow release so you might expect nutrients would not be available in the short time the seedling is in the pot but I have not found this to be the case. I also find seedlings establish very well outside after this treatment, probably because they still have slow release nutrients sustaining them for the week it takes for their roots to settle in and the fact the seaweed meal helps them with their immune systems.
If you have seedlings struggling in a low nutrient compost and they are too small to pot on, give them a low strength liquid tomato feed which should perk them up.
Cabbage Root Fly Above you can see some calabrese growing under insect protection mesh to prevent the cabbage root fly laying her eggs around the stems. As I am sure you know, the eggs hatch into maggots that burrow down and eat the roots, usually killing young plants. You will also know that the root fly is a problem with all brassicas (cabbage family plants) like cababge, calabrese, broccoli, Brussels sprouts, kale, turnip etc...
I am just making the point (because I just got caught out myself) that the root fly doesn't care whether the plant is in the ground or still in a seedling tray, she is happy to lay her eggs either way. I ended up with egg on my face the other day when filming our kale and swede video when I discovered most of may seedlings had root fly before I had even put them in the ground. In future I will make sure my seedling trays left outside are also covered with insect mesh.
Nutrient deficiencies in tomatoes When looking at plant feeds last week, we touched on nutrient deficiencies so the above image of a tomato issue, taken 2 weeks ago, might be of interest. The photo includes a much better shot of my thumb which, judging but the white patches on my nail, also shows nutrient deficiencies (zinc) in myself as well as the tomato.
The purple leaf colouring is most likely phosphorous deficiency which is unusual in my soil as it is deep and fertile. Interestingly, the cold start to the the year may have been to blame as tomatoes can have difficulty absorbing phosphorous if the soil is too cold (below 15˚C) which has been the case until recently.
I took the image above yesterday showing an almost complete recovery after temperatures have increased over the last 2 weeks. Stupidly, I had also applied a liquid tomato feed so I can't say for sure but, considering the rest of the tomatoes suddenly took off (no purple leaf or feed applied), I reckon the extra warmth did the trick. As regards my own deficiencies, I haven't taken any extra feed yet but I understand oysters will do the trick.
By the way, if you are growing tomatoes in a greenhouse or tunnel, it is highly likely that the lower leaves are curling inwards (mine are anyway), this is generally nothing to worry about as it is caused by significant flictuations in temperature. Until recently, it would have been reasonably warm undercover when the sun was out but could also be very cold at night making leaf curl very likely. From now on, younger leaves should be fine, but as lower, curled, leaves age, they can be removed and added to the compost heap.
Keep celery watered It is difficult to grow celery well and, to be honest, virtually impossible to grow the thick and juicy stems bought in the supermarket as they are grown under strictly controlled conditions. The advantage of homegrown celery is it has more flavour so adds more to soups and stews but is not so good eaten raw.
The trick with celery is to NEVER let it dry out or it will get tough and stringy, it is, of course, originally a marshland plant. Certainly in my garden, drying out of anything is a rare occurrence but if it does happen, it will most likely be in June. Above you can see celery Victoria looking very happy in the early morning sun, if the weather stays dry I will give it a good daily soaking early in the morning or in the evening to make sure I loose as little moisture as possible to evaporation.
Earthing up potatoes Above and below you can see the difference in growth in my early and maincrop potatoes. This is hardly surprising as they were planted nearly 4 weeks apart, at the beginning and end of April respectively. The process of 'earthing up' involves adding more soil, compost or other organic material around the potatoes to avoid them pushing through the surface and being exposed to sunlight. Tubers left in full sun will become progressively more green due to the compound solanine which also makes them mildly poisonous.
Earthing up can be as simple as dragging the surrounding soil or compost up around the plant or, if you would prefer to add extra material, using seaweed, compost, straw or grass clippings. Adding more garden compost (or envirogrind) is probably the best option because it will feed the potatoes and improve the soil for the following crop.
Potatoes push through the surface of the soil as they bulk up because the soil above them is less dense than the stuff below, they basically need more room and, as Yazz and the Plastic Population said in 1988, 'The only way is up'.
Early potatoes rarely need to be earthed up as the potatoes don't get large enough to breach the surface but you should always cover maincrop varieties. Early potatoes will most likely to be out of the ground by the time late blight hits in July and August but maincrop varieties will also benefit from the extra layer of soil or compost as it makes it less likely that blight spores washed off the leaves will reach the tubers below.
Deep planting leeks This image shows deep planted leek seedlings which I put in last Friday. These were the plants which I sowed in fish boxes (at the end of March) and have been growing in the polytunnel. The leeks are planted out as bare root transplants when they were about pencil thick with the majority of the plant ending up underground.
The idea of deep planting (15cm deep) is to bury a portion of the stem and exclude the light which keeps it white. I am not big fan of this method as it is fiddly and means the roots end up below the most fertile layers of soil but I wanted to feature it in the video for our new online course. It will be interesting to compare size and flavour with leeks I have planted at a standard depth.
The reason the soil isn't filled in around the shaft, by the way, is to avoid (or try to avoid) getting grit getting between the leaves and the layers of the finished leek.
Broad beans Broad beans are flowering now so will soon start to produce beans which herald the start of the summer pea and bean season. Broad beans are underrated in my opinioin with a better flavour than french or runner beans and a very pretty plant with their layers of sweetly scented flowers with lilac and pink centres.
Once the flowers have been produced the plants will be close to their optimum height (1 metre in the case of 'Witkeim Manita' pictured) and can have their tops (growing tips) pinched out and used steamed or in salads. The growing tips often become infested with aphids in June and July so removing them will also reduce the chances of an attack.
Maincrop peas Here you see a not very tidily arranged pea support mesh and a crop of 'Greenshaft' peas beginning their scramble up the poles. The mesh will be covered very quickly now, they are nearly covering a rung every couple of days with flowering to follow and, I expect, the first peas in early July.
You can also see Oriental spinach 'Mikado F1' growing alongside the peas, remember your beds need not be reserved for a single crop; many plants are very happy together, and sometimes do better, when grown side by side.
Polytunnel carrot harvest I have started to harvest my polytunnel carrots now as I need my beds for dwarf French beans and courgettes and I am glad to report they have very good. I had thought I was in trouble 2 weeks ago as one or two carrots started running to seed (this is always a risk with very early sown carrots sown under cover) but so far, very few have followed. The variety is 'Amsterdam forcing' (you must use a forcing variety when sowing early) which, as you can see, produces long, tapered roots. If I was able to leave them longer they would bulk out a bit more but I think it is highly likely the rest will go to seed if left for much longer.
I don't need to pull the entire bed but rather harvest from the areas where I want to put in my new crops. This might sound obvious but when a new seed or seedling goes in, it only needs it's immediate area vacant to get established; previous crops can be left to grow on for a period before the space is required by the roots of the new crop.
What to sow in June: Many people tend to think if you haven't got the vegetable garden well established by June, you have run out of time. This couldn't be further from the truth as there are still a wide range of summer, autumn and overwintering crops you can grow. Remember growing is a yearly cycle, you can jump on at any stage and still have plenty to do whether it is growing in the summer or preparing the garden in the colder months.
Crops to sow for summer & autumn harvest include: Basil, beetroot, broccoli calabrese, carrot, Chinese cabbage, coriander, courgette, cucumber, kale, kohl rabi, lettuce, mini cauliflower, Oriental salads, pak choi, florence fennel, french beans, parsley, perpetual spinach, radish, runner beans, spring onions, spinach, swede, swiss chard, turnip.
Crops to sow for overwintering include: Purple sprouting broccoli, kale, spring cabbage (don't sow until July/August).
That's about it for now. I am on holidays next week so will take a break from the mailer but there will be plenty to talk about when I get back to the garden the following week.