Autumn herb tips – treat ’em mean, keep ’em green

In life sometimes, you have to be cruel to be kind. And this goes for herb plants too.

Can you imagine standing all night long  in winter, with your bare feet buried in cold, wet, compacted soil? “But I’m a person, not a plant!” you’ll retort. True. Just trying to give you a bit of empathy with your herb plants – many of which originate from sunny mediterranean hillsides, and won’t thrive in chillier climes if you water them late in the day, especially when autumn night temperatures begin to drop. Even if it’s one of those hot old Indian summers, and your basil looks like he’s gasping for a drink at 5 in the afternoon – don’t do it – it’s too late. You might feel cruel, but he’ll thank you in the morning. The same goes for all the other mediterranean herb species, such as thyme, rosemary, sage, oregano etc. Water well when it’s hot, but water early.

Basil, is of course, an annual, so he’s not going to make old stems anyway. You can keep him going for as long as possible, by pinching out and picking regularly to prevent flowering, by watering before midday, by not transplanting (which can cause the plant to bolt), and by giving protection from the midday sun (ditto).

Sweet, fussy basil - but he's worth it. Use a glut of tatty old leaves in home-made pesto

It’s true – basil is a bit of a fusspot. But the reward is clear, when you’re chomping down on ciabatta topped with tomato, mozarella and freshly torn basil – because he’s worth it. Use up a glut of tatty old basil leaves by whizzing them up with garlic, parmesan, pine nuts and olive oil for home-made pesto sauce. Or make some basil oil. See Jekka’s Herb Cookbook for some gastric-juice-inducing basil recipes.  Hurry now though – as soon as the firsts frosts come, he’ll be gone. If your basil has gone to flower, harvest the seeds for future sowings. If basil’s in a pot, bring him inside and pop him on the kitchen windowsill to prolong his life.

Many thyme, rosemary, sage, and oregano varieties are fully hardy perennials (thyme and rosemary are also evergreens, so you can harvest them all year round).

Harvest Thyme - all year round

So, in theory, they should survive winter temperatures down to about -15 degrees C. But if it’s an excessively wet, dark winter, they’ll suffer (like us all) if their roots get too cold and wet.

We grow them from seeds and cuttings on the farm in South Glos,  so they’re not raised to be fair weather plants, but instead to endure wind, rain, snow..and the odd (very odd, this year) spot of sunshine. But it’s worth remembering that these herbs are native to hot, dry, sunny climes and rough, sandy soil. You’ll find clumps of thyme growing wild and picturesquely on the mountains of Greece, and big, beautiful, rosemary bushes thriving on the plains of Spain.

So, don’t plant mediterranean herbs in clay soil. It has tiny particles which stick like glue when wet, which makes the soil heavy and difficult for roots to penetrate. Clay soil is also very moisture retentative, which doesn’t make for good drainage. One benefit of clay soil is that because it’s so sticky, it is more likely to retain nutrients. But these mediterannean herbs are used to surviving on very little food and water and too much will spoil the plant and damage the flavour. A raised bed is one solution. Or plant in a pot. But if you absolutely have to plant thyme in clay soil, then improve it first, as good drainage is essential to prevent cold, continuously wet roots: dig in horticultural grit, sand, organic mulch to break it down. Autumn gives a perfect window of opportunity for soil improvement – once you’ve tidied up the beds, harvested your autumn berries

Myrtle berries - harvest in late autumn

and roots,  and sown your autumn salad herbs (under protection), planted your hardy perennials (which will put all their efforts into establishing healthy roots over winter before spring growth) there’s not much else to do in the garden. So, plenty of time to dig. Warms you up too.

PS – we’ve just been featured on, in their latest ‘Best of the web’ – hoorah!

© Jekka’s Herb Farm,  October 2011. Unauthorized use and/or duplication of this material without express and written permission from this blog’s author and/or owner is strictly prohibited. Excerpts and links may be used, provided that full and clear credit is given to  Jekka’s Herb Farm with appropriate and specific direction to the original content.