In 1918 the Swiss nurseryman Frikart produced the first commercial Aster amellus x Aster thomsonii hybrids. Those and the few subsequent hybrids are known as Aster x frikartii and include the ever popular ‘Monch’. All of the named cultivars make very good garden plants exhibiting the hybrid vigour which makes them much stronger and longer lived than either parent. The large starry flowers cover the plants from midsummer well into mid-autumn. Staking is not necessary unless the taller varieties are sited where they need to look tidy. All are completely resistant to mildew, and whereas wilting caused by verticillium can be a problem in A. amellus it doesn’t appear to affect A. x frikartii cultivars. ‘Jungfrau’ and ‘Flora’s Delight’ make very good, long flowering container plants. The pots should be put in a cold greenhouse or polytunnel from late winter until early spring to prevent damage from frost or excessive wet.
Plant in an open and sunny position, however, light shading until mid-day seems to do no harm. They prefer an alkaline soil with good to sharp winter drainage to ensure good root formation. If your soil is of a heavy clay inclination plenty of grit should be added to improve the drainage, or even as in our garden the creation of raised beds.
The clumps should be divided every three years in the early spring, just as the shoots reach ground level. Divide into 7.5 cm - 10 cm sections, and re-plant in well prepared ground. It is quite possible to re-plant in the same site although moving even just a foot or so will avoid any possibility of nematode problems. Leave 30 cm -45 cm between plants of ‘Mönch’ and ‘Wunder von Stäfa’ and about 30 cm between other varieties.