This lecture is suffixed “in a British garden” as obviously all orchids are hardy where they are natives. Hardy in this case means either planted outside, kept in a cold frame, or in a cold greenhouse. In many cases a combination is used. The myth that they are expensive and hard to grow is unfounded. They are now propagated by the thousand in European laboratories, and with many easy growing hybrids being propagated they are now in reach of the general public, and several mail order businesses stock them.
It is illegal to collect orchids from the wild – you can only do this with a license. Plants imported from Europe don’t need CITES and this is the main source of Jeff’s plants (Sweden & Germany). The conditions required are quite simple, however, experts often tend to over complicate their requirements from their natural habitat. Sunny borders, rockeries and raised beds, shady areas and unfertilised meadows are all quite adequate once you know a few simple facts about the type of plant that you want to grow, and this depends on the dormancy period. Getting this wrong means that heat is just as dangerous as severe frosts. 4 types of plant groups are found in the UK;
- Rrhyzome, winter dormant
- Finger tuber, winter dormant
- Oval tubers, summer dormant, winter green
- Psuedo bulbs, semi dormant
They generally prefer poor soils – that is the way that they have evolved. Neglect is part of the key to success, as it is easy to kill them with kindness. Some like limestone soils, others suffer through periods of drought and may well miss growing for a year (or more). Fungus isn’t as vital to these plants as many will have us believe although it is useful to help germination. Gritty soils help drainage which is a major benefit.
Dactilorhyzas are definitely garden worthy plants, and are some of the easiest to grow. This is a finger (dact) rooted (rhizome) plant that stores energy in the tuber to support the next years growth. Ideally these are planted in large clay pots buried in the ground to avoid drying out, especially in winter. They need to be damp at least, but not waterlogged. They will survive in a range of conditions from full shade to bright sun, and from pond margins to old meadows. You need to understand a bit more of the plants habitat to determine where to grow them. fuchsii, purpurella (northern bog orchid) and praetermissa (southern bog orchid) are UK natives from damp areas, foliosa is from Madeira, elata from North Africa, and sambucina from the alpine meadows.
Bletillas come from Japan and Asia, and have psuedobulbs. They flower in Spring/Summer, and benefit from more fertile soils to aid flowering – soil & loam is good. Sun and dappled shade is required. They spread outwards, and should be divided in summer to settle for winter. striata is the most common and cheapest and generally these are purple to white, with ‘Soryu’ being bluish, and ‘Junpaka’ white, ochracea is a yellow to cream species, and a growing number of hybrids is also available.
Cypripediums have a long rhizome mat of roots, and have long winter dormancy after dying back in the middle of summer. They flower usually between April and June. calceolus is the most famous – or is it infamous, and has been the subject of a covert reintroduction plan. This is a lime loving species (as the name suggests). Some of the other species can be difficult, but many of the hybrids are quite easy to cultivate – Ulla Silkens is one of these, and can form a clump outdoors of over 100 blooms within 10 years. Generally the flowers are on short spikes and last up to 5 weeks if kept cool. Plants are best grown in pots buried in the garden to avoid drying out too much. They should be in a mix of bark, grit, perlite, pumice and leaf mould (beech). Feed can be Tomarite used fortnightly. Avoid winter rain to avoid compaction, and don’t mulch. Easy species are the American reginae and parviflorum, and the Asian macranthos and tibeticum.
Wintergreen species are generally found in meadows, and are summer dormant. They start growing in the autumn, and shoot away in spring, flowering and setting seed then dying off as they are overcome by larger herbs. After 18 months in flask, they take 4-5 years to flower. They prefer free draining alkaline soils that are nutrient poor, and don’t like being frozen in small pots. They are often naturalised in lawns, which means no mowing until July! There are a small range of British and European species available, with pyramids and twayblades mainly available. Try to buy them after at least 2 years in soil. Use slug pellets to avoid the plants succumbing to a tasty meal. Orchis morio (pyramid) is the easiest UK native along with mascula and anthropophora. The bee orchids are difficult to grow well and also propagate. They tend to disappear for a year when it suits them. Ophrys apifera is a UK native of chalk downs. A variation on the bees are the spider orchids (still Ophrys), and fuciflora and sphegodes are a selection. Sadly these can go dormant for up to 7 years! Other species such as morisii and speculum need a cold house to grow best as they hate the wet, but you also need to avoid winter sun to prevent drying – difficult plants. In the right areas they can grow well – as they do in the wild. They are small and interesting, but need some care, and are very slow to multiply.
Other hardy genera include Platanthera bifolia, Gymnadenia conopsea, Himantoglossum hircinum (lizard or goat orchid), as well as the more common Epipactis palustris & gigantea, and Spiranthes cernua.
The final group covered were the hardy Calanthes, and there are 6 species from Japan that fall into this category (and their hybrids). They are semi-evergreen plants that grow in mountain woodland alongside ferns and hostas. They grow well in an organic mix, and need a reasonable feed during growth. They flower as the leaves open. The best known are sieboldii – a yellow species, tricarinata – green with a red lip, and reflexa – pink.
In summary, they are easy growing and cheap to grow as long as a few simple guidelines are followed. Find out what conditions are required for the plants you want to grow, and follow them. Pots and raised beds are important. Avoid winter rain, but don’t over protect them. Start with easier growing plants, preferably mature ones. When the bug strikes, but some more. Most of all enjoy growing them.
A few questions followed, and a good round of applause followed.