As you know, September is about the final act in the vegetable garden when we harvest many of our crops and prepare the soil for winter. This week I have had a quick run around the garden to check in on some September crops and to look at some of the plants that are going to tough it out through the winter and into next spring. As always it doesn’t include everything but hopefully it will give you some tips on the vegetables you may be growing now or are thinking of growing next year.
More on seed saving
I briefly mentioned last week that I have been growing the Italian bean ‘Borlotto Lingua di Fuoco’ for dried beans this year which prompted a few questions so, although we covered this already, I have included some more detail below.
One of the questions was whether the beans can also be used for seed next year to which the answer is yes. Unless you are growing an F1 Hybrid variety, the only reason you wouldn’t save seed from any plant was if it had cross pollinated with another variety (because the resulting offspring would be a mix of the two parent varieties or not ‘true to type’). While runner beans and broad beans will cross pollinate (with other runner or broad bean varieties, not with each other), French or Borlotti beans will be highly unlikely to cross so even if grown in close proximity should produce ‘true to type’ seed.
Growing for seed
As with any plant you are growing for seed, it pays to be particular about the quality of the plants you are saving seed from. I would use only the strongest looking plants and pick the best looking pods rather than using the last stragglers at the end of the season. For this reason it is better to leave the plant unpicked until the seeds are ready to harvest as the first crop of beans will be be of the highest quality.
I grew my borlotti in the polytunnel so was able to pick the pods when dry and papery but, unless you have a very sunny Autumn, it will be better to harvest when the pods are still yellow/green and bring indoors to dry. If you have a lot of beans to process, it is better to bring in the whole plant with beans still attached and hang in an airy shed. If not, they can be dried in single layers in crates or trays.
As in the photo of above, once beans are ready for storage, they need to stay dry so it is also a good idea to either put a layer of dry rice in the bottom of the jar or use a silica gel pack to absorb any extra moisture.
Autumn is real treat for me because I love the aniseed flavour of florence fennel which is coming into its prime harvest time now. You will often hear that bulb fennel (as distinct from herb fennel grown for its leaves) is difficult to grow because if its tendency to run to seed but this is most often due to it being sown at the wrong time of year rather than a fault with the plant.
Fennel is programmed to flower in early to mid summer so while you can grow it in spring, you need to be on the ball and harvest quickly before it tries to seed. Summer sown crops that mature in Autumn are a lot less stressful to produce as the bulbs will stand in good condition for much longer because the urge to flower is not there.
Fennel is ready to harvest when the bulbs are about 8cm across (the one in the background is ready, the smaller one is a second crop sown 2 weeks later so will be ready in another couple of weeks). To harvest, cut the bulb at ground level and leave the roots in the ground, they won’t re-sprout and will provide food for your soil life as they rot down.
What is a simple and delicious florence fennel fennel recipe? Slow roasted with cherry tomatoes and caraway seeds.
Leek Succession Sowing
Above you can see leek ‘Musselburgh’ sown at the end of March and now coming very close to harvest time. I sowed leeks on 3 dates this year, early March, late March and early May in order to have leeks in late summer, autumn/winter and early spring. I am not sure I will bother with the early sowing next year as leeks in late summer aren’t very exciting (there are so many other delicious crops to choose from) but winter leeks are a fantastic crop which can be harvested right through to early April next year.
The leeks above are my 3rd sowing ‘Blue Solaise’ which are an ideal over wintering variety. It is not always the case but overwintering leeks tend to be more of a blue/green colour and have more of a stubby shaft than the earlier varieties; the shorter shaft is handy because taller leeks are more likely to suffer from frost (which can lead to rot). Once temperatures rise in March, overwintering varieties put on a spurt of growth and produce a longer leek but you need to keep an eye on them as they will also be close to running to seed.
No big revelations on carrots but a nice photo for a bit of colour, these are ‘Rothild’ sown at the end of May or early June. The only thing I would say is that, if growing carrots, remember that the second generation of carrot root fly is active from August until October so I would make sure to keep the crop covered with insect protection mesh. it can be easy to let your guard down at this time of year as we are harvesting maincrop carrots but, if we don’t lift and cover again quickly, carrots pulled later in the harvesting period will very likely be ruined by root fly maggots.
Winter members of the cabbage family are one of the other stars of the winter garden. Unfortunately if I had a penny for every September email asking if it is too late to sow Brussels sprouts I’d be a millionaire so, disappointing if you haven’t sown them but great if you have.
The image above is of sunlight through the leaves of crinkled savoy cabbage (‘Vertus’) as it begins to form its heart, I would be expecting to harvest full heads by late October. One of the great advantages of winter cabbages over summer varieties is, once the cold weather arrives, they will sit in the ground without degrading until they are needed (whereas spring and summer varieties will bolt or split). Also, there are very few pests around from November onwards so you don’t generally need to worry about them being eaten by something.
Dense ball-head or coleslaw cabbages like the red cabbage above can be damaged by a hard frost so are better cut and stored in November and will keep for several months in a cool dry shed. Cabbages that stay in the ground for winter like the savoy above or varieties like red/purple blushed ‘January King’ form looser heads which aren’t damaged by frost so it is worth getting to know your varieties to find the right one for the time of year you want to harvest.
You will also find, by the way, that stored cabbages keep better if harvested with their roots intact rather than cutting them off at ground level as there is no wound that may be an entry point for disease. If a scruffy root is too much to bear, at least leave 15cm or so of stem so if rot does set in it will be 15cm away from the cabbage heart and give you time to spot it and do something about it.
Feeding winter brassicas
It is late to feed winter brassicas now but if they are not thriving in early September, it will be worth giving them a pep up so they can bulk up while there are still some relatively warm days left. As time is of the essence, you are better off giving a liquid rather than a granular feed as it will have the quickest effect. A liquid comfrey feed is a good option.
Also, and I know I keep going on about it, stake and support tall brassicas like Brussels sprouts and sprouting broccoli. Purple sprouting broccoli especially as it gets very top heavy and is easily rocked about by the wind. Wind rock breaks fine roots and can lead to premature flowering (and thus lower yields) so the 5 minutes it takes to push in and tie a stake is very worthwhile.
Speaking of premature flowering, broccoli calabrese will head up early (again resulting in smaller heads and lower yields) if it is short of water. Pictured above is my last crop of calabrese for the year which it would be unusual to have to water in the Autumn but needed it because it hasn’t rained for nearly 2 weeks. Like all the top growers, you can see I have a water emitting thumb which is very handy for this purpose.
If you are growing calabrese over winter in a polytunnel or greenhouse (for heading early next Spring), make sure to retain some moisture in the soil especially early next year for the same reason. Because we water so little in winter, it can be easy to forget and let it get dry which can be an issue when plants resume growth in February.
Should you keep feeding tomatoes?
We get asked a lot whether you should stop feeding tomatoes at this time of year or keep going until the end of the season. In my opinion, if tomatoes are grown in beds of a decent size and are in a fertile soil, they should not need any extra feed, indeed, if the soil is well fed with well rotted manure or compost before planting, they shouldn’t have to be fed at all.
Container grown plants are different because all their nutrients come from such a small and relatively infertile volume of compost. As I probably said before, I would feed container plants every two weeks from the flowering stage onwards but once we get to late August and early September I would cut back. Any new fruit produced at this stage will not have time to ripen before the first frost so applying a feed to promote fruiting will be a waste. As we said a couple of weeks ago, the focus now is on ripening existing fruit rather than new growth so, as a fertilizer promotes growth, again it isn’t needed. In short, my last feed would be early September, also cut back watering to the minimum, it will give more intense flavoured fruit.
Pruning raspberry fruit
If you haven’t done so already, now is the time to prune out the old raspberry wood and to tidy up new canes if your rows are getting overcrowded. Pruning of old wood is much easier to do now rather than waiting until the winter as is easier to tell which stems are new and which are old.
As you can see in the photo the new growth is a vibrant green while the old is brown and woody looking; this will all be brown in the Winter so more difficult to tell which is which. I will be pruning all the brown wood right down to the soil now and also cutting out any excess new green wood to leave 6-8 strong new stems per plant.
I will also be removing any new shoots growing outside the 2ft width of my raspberry rows, these ‘suckers’ are best dug out as pruning will result in more canes where I don’t want them. I will leave the tops of the canes alone until February when I will prune them to about 6ft high.
That’s it for now, I will see you next week!