Twitter hour Monday 27th February hosted by Gill Hodgson@thepatientmole and Mike Rogers@sofaflyer notes by Jill Smith@binningtonbloom
Successional sowing means that as a batch of flowers comes to an end you have another bed ready to start cutting – at least that is the theory. However as the discussion unfolded it appeared that achieving the longest flowering period possible could be obtained in a variety of ways.
Hardy annuals respond to successional sowing best, sow first in autumn, again in March and then in May.
Half hardy annuals do not respond as well, antirrhinums can manage two sowings but flowers which are long day dependant will probably only produce good flowers from one timely sowing eg. Cosmos
Some flowers respond well to constant cutting to keep on growing so reducing the need to repeat sowing eg. clary sage. While others just get weaker the more you cut eg. cornflower and respond better to successive fresh sowings.
Another form of successional sowing is to keep sowing not necessarily the same flower but the same type eg. spike/daisy/lace
Sweet peas are recommended to sow in October, February and April. The October and April sowings can be in a polytunnel and the February sowing for planting outside.
Don’t succession sow at too close an interval, such as every two weeks, as this often results in them all flowering at once.
Quick germinators, such as Nigella and Cornflower will flower from a July sowing in mid October, if you are lucky.
Some annuals will regrow from being cut right back after the first flowers, eg. scabious, this will take about 2 months to the next flush of flowers.
Perennials can be prolonged by giving part of the patch the Chelsea chop ie. chop back growth severely in late May so that the regrowth results in a later flowering. Alchemilla mollis is ideal for this.
Some flower varieties were just not recommended for any sort of successional sowing – feverfew, sweet william, orlaya, gypsophila.