Action plan: Nigel Colborn’s essential jobs for your garden this week
- Nigel Colborn says there’s just enough time to sow seeds for salad leaves
- Fast-growing leaf plants include rocket, spinach, pak- choi and radishes
- UK-based gardening expert says prepare a crumbly seed bed if sowing in ground
STILL TIME FOR LEAFY GREENS
Days may be shortening, but September can feel like a second spring. If you sow seeds forsalad leaves now, there’s just enough time to produce delicious fresh salad leaves.
Fast-growing leaf plants include rocket, spinach, pak-choi (pictured), radishes and even soft-leaved brassicas.
Outdoor temperatures are still warm, so you could sow seeds of half-hardy coriander or even deliciously aromatic basil.
If sowing in the ground, prepare a good crumbly seed bed. In dry weather, keep the soil watered. For containers, use good quality peat-free potting compost. This is also the season for planting out spring cabbage. If grown from seed, that should have been sown before mid-August. But there’s still time, provided you sow your seeds this weekend. Sowing in a greenhouse might produce baby plants more quickly.
Gardening expert Nigel Colborn, says there’s just enough time to sow seeds for salad leaves
Young cabbage plants should be ready to set out four to six weeks after sowing. You can also buy spring cabbage plants from good nurseries and garden centres. They’re more expensive than seeds but would make your planting more timely.
For all autumn-sown seed, sheltered spots in full sun are best. Frosts are unlikely before October, except in cold areas. But if you have vulnerable seedlings, having some horticultural fleece handy could save them from overnight damage.
KEEP GRAPES SUNNY
Thanks to our warmer climate, I’ve been harvesting outdoor grapes every autumn. My vines are trained on a south-facing wall, but excess summer growth has shaded the fruits. To fix that, I remove newly grown stems and leaves. To prevent vines bleeding sap, I clip the thinner stems. On the long, thin shoots, I pick off as many leaves as necessary. The bare stems can then be winter pruned, when sap is not rising.
FRIENDLY LAWN FUNGI
Autumn brings mushrooms, toadstools and fairy rings. Those may concern people who fear honey fungus, a serious disease which can attack shrubs and trees. But toadstools in grass or under trees are often harmless. The fairy rings or mushroom growths are fruiting bodies of a vast underground fungal community, indicating that your garden soil is healthy. Soil-born fungi are essential for plants, enabling them to absorb the minerals they need.
Nigel says late-blooming varieties of Ceanothus are among the best shrubs that flower in September
PLANT OF THE WEEK: CEANOTHUS ‘AUTUMNAL BLUE’
Shrubs that flower in September are to be treasured. Among the best are late-blooming varieties of Ceanothus, particularly the variety Autumnal Blue. Also known as Californian Lilac, the shrub grows to 3m. Smoky sky-blue flowers appear from late summer and continue well into autumn. The glossy evergreen leaves make an attractive background for those. Though hardy, this shrub grows best against a sunny wall or sheltered space. Ceanothus can resent pruning. So avoid that, other than cutting off spent blooms.
My neighbour says I have ragwort in my rough grass and that it’s illegal. I know it’s poisonous, but is it illegal to let it grow? Bees and butterflies love it. Also there are black and yellow caterpillars feeding on it.
J. Holdsworth, via email.
Landowners are required to control ragwort only if it grows 50 metres or less from land used for forage or for grazing livestock. Being highly toxic to horses and a risk to grazing animals, that rule makes sense. Ragwort, despite being toxic, is beneficial to wildlife and pollinators. The caterpillars are larvae of the beautiful red and black Cinnabar Moth. They absorb the plant toxin which protects them from predation. The black-yellow bands are warnings to predators.