September Gardeners’ Blog
During September, the indoor team will be busy potting spring bulbs in the nursery, looking to use them in the Mediterranean House next spring. Hyacinths will be planted in 13cm half pots, 3 bulbs to a pot, each with their noses protruding out of the compost so that they don’t rot. Meanwhile, Daffodils will be planted in 18cm pots, 7 bulbs to a pot. Once this is complete, the Hyacinths and Narcissus will be placed outside in a north facing, dark covered cold frame until late winter. The cold and dark is needed to initiate good root growth.
Outside, the team will be planting spring bulbs in our bedding displays. This will be done once the 4,000-winter flowering Polyanthus has been planted out first. The gardening team will also start discussing, choosing and ordering around 10,000 to 12,000 bedding plants for the next 18 months. Yes, for summer 2019 and winter 2019/2020! Gardeners always have to plan ahead!
Moreover, if you’re looking to create your own horticultural getaway, remember that now is a great time to propagate tender plants, ready for next year’s display. Coleus, Pelargonium (geranium) and Salvia can be propagated by cuttings now and will become a good-sized plant before the weather turns cold. For the best results, take cuttings from healthy and non-flowering stems. They should be about 10cm long and cut just below a node, which is the part of the stem from which one or more leaves emerge, often forming a slight swell.
Once this has been done, remove the lower leaves to prevent them from rotting and pot them into a free draining compost mix. We recommend 75% multipurpose compost and 25% sand, grit or perlite. Then, make sure you water them when the compost is dry and place them in a warm shady place. Lastly, place a polythene bag over them to keep the humidity high and prevent them from drying out so quickly.
September is also the perfect time to divide herbaceous perennials, now that the weather is cooler and damper. After 3 to 5 years, perennials can get pretty big and can start getting woody – they can even die out in the centre and lose vigour. By lifting them and cutting them into smaller sections with a spade, it helps to rejuvenate the plant. Don’t forget to water them in well. You may find you now have too many plants – why not give or swap them with your family and friends!
Towards the end of the month, why not visit the gardens to see one the first trees producing autumnal leaves?