Cultivation

Growing nicotianas for the flower garden is a relatively easy affair. To get the most vigorous plants, you should grow them annually from seed, although there are some species that are perennial. In warmer countries, or in a heated greenhouse, they can make comparatively large, long-lived plants. They can be propagated from cuttings or offsets, even self-sown seedlings weeded out from the gravel beneath greenhouse benches will regrow from any roots left behind.

Seed should be sown thinly on to moist, light compost from February to March. The seed is generally quite fine, and should only be covered very lightly and kept under glass or indoors at around 18-20°C. Germination takes about a fortnight and is usually quite uniform. Seedlings should then be moved on individually into plugs or small pots as soon as they are large enough to handle. Make sure seedlings have been kept well-watered before transferring, this will help the small plants negotiate the stress of upheaval. It is also worth noting that tobaccos have brittle, clingy leaves that stick to one another and will rip or break if you don’t take due care while separating. Nicotianas are hungry plants, so avoid letting them become pot-bound or starved as this will pinch their growth and give you small, spindly plants.

Although tobaccos can tolerate mild frosts, it’s important to ensure a gentle transition from the heated greenhouse to the garden. Plants should be hardened off in a cold frame before planting out in late May. Even with the onset of warmer days, do keep an eye on overnight temperatures as a cold night can shock the growth of these tender plants – it’s much better to delay planting until the danger has passed and hit the ground running. Nicotianas will thrive in a deeply dug, light soil that has been improved with good compost. Water and feed as necessary through the summer. Slugs and snails can be a nuisance for young plants and make untidy holes in the leaves, also be cautious of aphids and whitefly, which will colonise both the flowers and foliage. Hot, dry weather can render the plants more susceptible to mildew and a fungicidal spray may be needed under these conditions. Nicotianas have strong stems and require little staking, but in an exposed position or in windy weather the plants may rock at the base, in which case a short cane would be beneficial to support the plants.