September plant of the month - a blue monk

'Mönch' ('monk' in German) is a well-behaved Michaelmas daisy that looks good with many other plants

Aster × frikartii 'Mönch'Aster × frikartii 'Mönch' is a hybrid between two species found in drier habitats than the damp-loving American species. As a result, it is happy in quite dry conditions and does not so easily succumb to wilt and mildew as do other asters.

In late summer and early autumn, ‘Mönch’ produces colourful yellow-centred, lavender-blue daisies, each with a double row of finely rayed petals, almost hiding the dark green foliage. It will tolerate dry conditions and poor soil, but flower size and height will suffer accordingly.

Aster × frikartii 'Mönch' AGM has a long flowering season, from mid-summer into autumn; and provided it is in a spot sheltered from the wind, it does not need staking. 'Mönch' is also very free flowering and easy to place as the colour associates well with many other summer and autumn flowers. The lavender-blue flowers are intensified by stronger colours, particularly orange-red and purple. It looks good with upright plants such as red or orange crocosmias and red-hot pokers (Kniphofia).

Aster 'Mönch' at RosemoorThere is just one word of caution – do not plant it in heavy clay. At Rosemoor, when we first tried this aster, a few plants were lost in our clay soil. It is important to adequately improve the soil with organic matter, as we have done in the AGM Garden and the Long Borders where it now thrives. 'Mönch' is also quite late to appear, so it is easy to dig it up thinking that it has succumbed.

No autumn garden is complete without Michaelmas daisies, especially cottage gardens or traditional herbaceous borders. As an added bonus, it is a fantastic plant for insects, especially bees, as the flowers are laden with pollen and nectar. We grow it in a partially shaded spot in the AGM Garden and on the Long Border where it is in a sunnier position and grows a little taller.

A variety of asters in pinks, blues and white will be found at Rosemoor Plant Centre including Aster × frikartii 'Mönch' (while stocks last), so there should be at least one of these lovely plants suitable for your garden.

See also

10 award-winning autumn grasses

Find other plants that attract pollinating insects to your garden

Locate aster suppliers

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