Winter Flowering Jasmine - Jasminum nudiflorum - are often seen as a straggly mass of untidy stems. Not too bad a description for the shrub generally. But, this can be changed by correct pruning of Winter Jasmine; at the correct time.
Simply cut back the flowered shoots, to below where the flowering started - as soon as possible after flowers have finished. Or, if grown as a close-cropped wall shrub, clip back the flowered growth with a pair of shears - once finished flowering.
This annual prune is really the only essential maintenance it will need. Without an annual trim, winter jasmine will develop many bare branches and become a tangled mess. With the annual cut-back, you can have beautiful arching sprays of gold - in mid-winter!
Cut back the flowered shoots to within a few cm of the older branch. Also cut back some of the older branches to within a few cm of ground level in order to promote more basal growth. To grow as a small arching shrub, prune each spring as for Buddleja.
In spite of the mass of stems, it will be seen that there is generally a framework of older branches in the winter jasmine, from which the flowering shoots grow. If there is not a framework of older branches - such as on a young shrub, it would be easy and preferable to leave a few of the slender canes and train them either up a trellis, along wires, or wherever you want your Jasmine to grow. It has the potential to grow 2m plus - so can easily be trained over a garden arch!
Cut back all the lateral shoots that have flowered, to no more than 4 or 4 in (15cm) from the main framework. This applies however you have chosen to grow your Winter Jasmine - even if you grow it as a hedge!
Winter Jasmine normally stops flowering in late February - sometimes early March. It then need much of the remaining year to make flowering branches for the next winter.
It is important to carry out the pruning as above, as soon as the shrub has finished flowering. Even if you see a few new twigs above where you need to cut, you should ignore those and cut back hard.
Jasminum nudiflorum will soon send out new fresh shoots, and these will start to develop their flower buds through July and August. Prune too late and the flower buds will not have enough time to develop on the new shoots.
The earlier you prune back, the longer tha arching sprays will be.