Launching into the C annuals I forgot two important annuals I grow every year.
Flowers are not everything and some plants make their mark with their foliage, form or mass of small flowers. If amaranthus only had a single flower per stem they would not be worth a single glance let alone a second one. But because they are massed into distinctive inflorescences they make a big contribution in the garden. Robinson wrote ‘Annual plants, some of distinctive habit and striking colour. The old Love-lies-bleeding (A. caudatus) with its dark-red pendent racemes, is a fine plant when well grown, but A speciosus and some other varieties are finer.’ … ‘The varieties of A. tricolor require a light soil and a warmer place.’
The amaranthus we value for ornament are plants from Central America and Quinoa is closely related. Amaranths have long been long valued for food and every part is edible. The leaves are eaten as greens and the seeds, rich in protein, are a staple in many areas. There are amaranths found in most continents and cuisines. As seen above the best known garden amaranthus is A. caudatus, with its long tassels, typically in deep red but also in green. Similar, but more bobbly, is ‘Dreadlocks’ (above). Most garden amaranthus have upright stems of flowers. While the flowers are tiny, they are surrounded by masses of (soft) bristles that remain attractive for many months. These are usually green, beetroot purple or shades of brown.
I hardly dare mention species or varieties because I think it is a minefield but most could be lumped under A. hypochondriacus for convenience and to get you started. They are fast-growing leafy plants with terminal inflorescences followed by sideshoots that bloom later and create a bulky, substantial plant.
Usually treated as hardy annuals that can be sown where they are to grow, I sow in cells. The small, usually shiny black seeds (though they can be buff or brown) are sown on the surface and they germinate within a week or two at about 18c. It is essential that the plants never suffer from competition or they will run to seed and not make the bulk needed to grow into large plants with substantial inflorescences. So as soon as the pinch of seeds has germinated I thin them to three and then just one seedling per cell. They can be planted out in late May so I usually delay sowing till mid April so the plants are still young and vigorous and not suffering from being starved. Amaranthus will take all the moisture and feeding you can give them so find a sunny place and a rich soil. They associate well with cannas and other subtropical plants and also make brilliant cut flowers.
But there are other amaranthus which are very different. Mostly variants of A. tricolor, these are lower, making rosettes of foliage, with bright colours, usually contrasting shades at the base of the young leaves. The most popular are red or orange but others are bright yellow. Looking rather like monstrous poinsettias, these are striking garden plants. The trouble is that they need plenty of sun, warmth and feed but also heat. Perhaps because I have never treated them as well as I should I have to admit that I have rarely had very good results with them. The only times I have was when I prepared the soil well, lavished water on them at first and we had a good sunny spell. I think they are amazing but not beautiful enough to risk time and effort on every year.
In contrast, the last A is something that not only do I like to have every year, it is something that I will probably have even if I don’t make any effort. Atriplex hortensis ‘Rubra’ (red Orache) is basically a fat hen on steroids. But unlike the related native fat hen or goosefoot the leaves on this hardy annual are a glorious rich burgundy colour. Although it will self seed it is easy to identify and remove or keep the seedlings. They are especially beautiful when young and when backlit. The photo below does not do the plant justice. In good soil and thinned to allow good growth they can reach 2m high. When mature the stems have smaller leaves and produce tiny flowers followed by seeds, all the same wonderful shade. An added bonus us that, like amaranthus, atriplex is edible. Amaranthus leaves, although recommended as salad leaves, sometimes have rather rough hairs and I don’t find them very palatable. If I made the effort to find a good recipe I am sure I would like them more. But atriplex is a different matter and I use thinnings raw and cooked and they are very tasty. Seedlings will vary in colour and I usually find some that are greenish – which are eaten and not allowed to seed, but also golden-leaved seedlings with red stems that are very exciting.