How to grow
As noted above, abutilons come in a variety of shapes and sizes and lend themselves to different situations and methods of cultivation, either in the garden or as pot grown specimens. Abutilon Vitifolium and Abutilon x Suntense form largish upright shrubs and can be grown as freestanding specimens in the garden or against a wall, preferably in a sunny position sheltered from the wind. The hybrids derived from Abutilon Megapotamicum, such as Kentish Belle, can be quite lax and floppy in their growth habit and so are best suited to growing against a wall or fence, again in a sheltered position. The bushy forms of Abutilon x hybridum can be planted as freestanding specimens, but we favour growing them in a large patio pot, which allows you to move them around outdoors as you wish from spring to autumn and then placed in a sheltered corner or brought into a greenhouse or conservatory when winter arrives. They will often continue to produce flowers through the winter if brought in out of the cold.
Abutilons need a well drained soil so, if planting in a pot, use a good quality John Innes number 3 or similar with the addition of some horticultural sand and/or grit to avoid waterlogging of the growing medium. We have our own recipe, based on a high proportion of coir, which works very well for us. They are greedy plants - unsurprising, given the length of the blooming season - so from spring to autumn you should feed them with a liquid fertiliser every couple of weeks. Alternatively, use something like Vitax Q4 early and mid to late season.
Abutilons are fairly trouble-free things to grow, but indoor plants can suffer from whitefly, to control which there are a number of organic treatments on the market. Snails - particularly juvenile ones - are not adverse to climbing up an abutilon and munching on the leaves: if you see shredded foliage, that’s your likely culprit. Other than that, there’s not much to worry about.
How do I grow abutilons?
Not a straightforward question to answer and made more tricky by the fact that we live in south Hampshire (in a sheltered spot) which is prime H3 territory (H3 is one of the RHS’s hardiness ratings). They rate abutilons as either H2 or H3 depending on variety, which means some will need bringing in or protecting once temperatures reach 0C and others will take -5C. But these are but rough assessments and much depends not just on where in the UK you live, but also the micro-geography of your garden and its consequent micro-climatic conditions. As a rough rule of thumb, an occasional light frost is unlikely to do much damage, prolonged frosting may cause leaf loss, severe frost or freezing conditions for periods of 24 hours or more may kill plants. For example, the Beast from the East of a few years ago, with its temperatures down to -10C and prolonged snow cover, did for unprotected abutilons here on the nursery that had survived normal winters problem-free. Covering outdoor plants with horticultural fleece is therefore advisable if the weather forecast suggests freezing temperatures; fleece can be left in situ for a period of time without any problem. Abutilon Megapotamicum and hybrids based on that species are, in our experience, generally hardier than most and can often take -5C to -8C in a sheltered position. A. Vitifolium and A. x Suntense are hardier still, usually being able to withstand temperatures down to -10C. But, as we say, it’s not an exact science, as there are various factors in play.