Sprekelia formosissima is the only species in its genus, a monospecific member of the Amaryllidaceae family native to the rocky hillsides of Mexico and Guatemala. It goes by several names: Aztec lily, Jacobean lily, St James's lily, orchid amaryllis. All of them hint at the plant's most remarkable feature: flowers unlike anything else in the garden, a deep crimson with an unusual cross-shaped arrangement of petals, three sweeping forward and three curling into a narrow tube, the whole thing resembling a tropical orchid crossed with a lily and saturated in the colour of old velvet. The flowers last about a week, and they are worth every minute of the effort involved in getting them.
In the UK, sprekelia is grown almost exclusively as a pot plant brought outside in summer and stored frost-free through winter. The leaves are strap-like and blue-green, similar in form to a hippeastrum, and they emerge either just before the flowers or alongside them. When the leaves curl, narrow, or look unhealthy, it is usually a sign that something went wrong during dormancy or that the bulb is not getting the summer conditions it needs. The two causes below account for the vast majority of problems.
Insufficient summer baking and heat
The single biggest limitation for sprekelia in the UK is summer temperature. This is a plant from the sun-baked slopes of central Mexico. After flowering and during the long summer growing season, the bulb needs sustained heat to ripen its interior and build the energy reserves required to form flower buds for the following year. UK summers rarely deliver enough of either.
The result is a plant that produces leaves quite readily but refuses to flower reliably. The leaves may look perfectly normal: broad, upright, healthy blue-green. The plant is not in distress. It has simply not been given the summer conditions it needs to set the flower bud that would otherwise open the following spring. Year after year of leaf growth with no flowers is the characteristic symptom.
The approach that works best in the UK is treating sprekelia exactly as you would a Mediterranean bulb. Grow it in a pot, using a very free-draining compost (a John Innes No.2 mixed with roughly a third extra grit or perlite works well). From late spring to early autumn, place the pot in the warmest, sunniest position you can find: a south-facing wall, a paved terrace that absorbs heat through the day, or a greenhouse with the roof vents open. Feed every two weeks through summer with a high-potassium liquid fertiliser to support flower bud formation.
As the leaves begin to die back in late summer, start withholding water progressively. This is the signal to the bulb that the dry dormant season is beginning, which is as important as the heat. Do not rush to cut the dying leaves: let them yellow and wither completely so the bulb can reabsorb every last nutrient before going dormant. Once the compost is dry and the leaves have gone, move the pot under cover and keep it bone dry until you see new shoot tips emerging the following spring.
Repot in fresh compost every two to three years. Sprekelia flowers best when slightly pot-bound, so resist the urge to move up to a very large container; a pot that is a few centimetres wider than the bulb is ideal. The neck of the bulb should sit just at or above compost level.
Overwatering during dormancy
Sprekelia has a hard dormancy that runs from when the leaves die back in late summer through to the following spring. During this period, the bulb needs to be kept almost completely dry. Any moisture reaching the bulb during dormancy creates the conditions for basal rot (most commonly caused by Fusarium) or other fungal problems.
The insidious aspect of dormancy rot is that the bulb can look perfectly fine from the outside while internally damaged. You store the pot dry through winter, return it to warmth in spring, wait for the characteristic shoot tip to emerge, and nothing happens. Or one or two very thin, pale, narrow leaves push up and curl over weakly before the plant stops altogether. When you unpot the bulb, the base is soft, dark, or hollow at the centre.
Prevention is straightforward but requires discipline, because the impulse to water a dormant pot is hard to resist. Once the leaves have fully died back, do not water at all. Store the pot in a frost-free space with some airflow: a cool but bright spare room, a frost-free greenhouse, a sheltered garden shed with a minimum temperature of around 8 degrees Celsius. The pot should feel light and the compost should be dust-dry. Do not water again until you see the first signs of new growth in spring, typically a pale shoot tip pushing up from between the old bulb scales.
If you do find rot when you unpot a bulb, cut away all affected tissue with a clean sharp knife until you reach firm, white flesh. Dust the cut surfaces with powdered sulphur or a copper-based fungicide and allow the bulb to callous in a warm, dry place for three to five days before replanting in fresh compost.
Other causes of poor growth
Frost damage is common and causes dramatic, rapid collapse of the leaves. Even a light frost will blacken and flatten the foliage within hours. Move pots inside before temperatures fall below 5 degrees Celsius in autumn. If caught by a late spring frost after new growth has emerged, the affected leaves will not recover, but the bulb itself may survive if brought inside immediately and kept dry until it attempts new growth later in the season.
Narcissus bulb fly (Merodon equestris) is a shared Amaryllidaceae vulnerability. The adult fly, which resembles a small bumblebee, lays eggs near the base of the plant in late spring and summer. Larvae tunnel into the bulb and consume the interior, leaving a hollow shell that produces no growth. Inspect the base of any sprekelia that fails to emerge: the tell-tale sign is a soft, lightweight bulb with a small entry hole and a larva inside. There is no rescue for a heavily infested bulb. Protect healthy plants by keeping pots on hard surfaces where the flies cannot reach the compost surface, or cover with fine mesh during the egg-laying season.
Narcissus eelworm produces stunted, puckered, or abnormally curled leaves combined with a characteristic brown ring pattern visible in a cross-section of the bulb. There is no treatment; affected bulbs must be destroyed and the pot and compost disposed of.
Red spider mite is a risk for sprekelia grown under glass or in a dry heated room in summer. The mite causes a dull, bronze stippling on the leaf surface and fine webbing in severe infestations. Increase humidity around the plant, check the undersides of leaves regularly, and treat with an appropriate miticide or biological control if populations build.
Vine weevil larvae are a hazard for any pot-grown plant. If a sprekelia suddenly collapses during the growing season with no other obvious cause, check the root zone for the characteristic white C-shaped grubs. Treat with a biological nematode drench applied to moist compost in late summer or early autumn.
Sprekelia in UK gardens
Sprekelia was introduced to Europe in the 16th and 17th centuries and was prized by Victorian collectors for flowers that looked like nothing else in cultivation. The Jacobean lily name reflects its early popularity in 17th-century Britain; it was fashionable enough to be widely depicted in botanical illustration and grown by the great garden designers of the period. That enthusiasm rather faded as gardening tastes shifted and tropical greenhouses fell out of fashion. Today it is an unusual find, available from specialist bulb suppliers in the UK but not generally stocked by garden centres.
This is a plant worth seeking out. The flowers open in spring or early summer, often appearing before or alongside the first leaves, and the effect is startling: a single stem bearing a bloom that looks simultaneously like a crimson orchid, a bromeliad, and something from a Renaissance botanical painting. The flower is about 12 centimetres across and lasts approximately a week. Each bulb typically produces one flower per season; a mature bulb that has been well managed for several years may produce offsets that can be potted separately once they reach a good size.
The most reliable approach for UK growers is full pot culture all year round. Bring the pot outside to a south-facing patio or the base of a warm wall in late May, give it a hot summer with regular feeding, begin drying off in August, and keep it frost-free and bone dry from September to March. Done consistently, this produces flowering plants year after year. The effort is modest, and the flowers make it entirely worthwhile.
Frequently asked questions
Why won't my sprekelia flower?
Failure to flower is the most common complaint with sprekelia in the UK. The bulb produces strap-like leaves readily but requires a long, hot, dry summer to ripen sufficiently for flowers the following year. UK summers rarely provide enough sustained heat outdoors. To improve flowering: grow in a pot, place in the hottest sunniest position you can find (a south-facing patio or greenhouse), begin withholding water in late summer as the leaves start to die back, and keep the dormant bulb completely dry through autumn and winter. Feeding with a high-potassium liquid fertiliser through summer while leaves are active also helps build the energy reserves needed for flower bud formation. A sprekelia that flowers reliably in the UK is one that has been treated like a Mediterranean bulb all year round.
Why are my sprekelia leaves narrow and curled rather than broad and upright?
Narrow, weak, or curled leaves emerging in spring usually indicate that the bulb was damaged during dormancy, most often by overwatering or basal rot. A healthy sprekelia produces broad, strap-like blue-green leaves. If the emerging leaves are thin, pale, or twisted, carefully unpot the bulb and check the base: soft, dark, or mushy tissue at the base indicates Fusarium or fungal rot. Remove all affected material with a clean, sharp knife, dust the wound with powdered sulphur or a fungicidal powder, and allow the bulb to dry in a warm place for several days before replanting in fresh, very free-draining compost. A bulb that is externally firm but internally damaged may produce very weak growth for one season and then fail to emerge at all the following year.
Why is sprekelia called the Aztec lily, Jacobean lily, and St James's lily?
Sprekelia formosissima has accumulated several common names, each from a different thread of its history. It is native to Mexico and Guatemala, which connects it to Aztec culture and gave it the name Aztec lily. It was introduced to Europe in the 16th and 17th centuries, arriving in Spain via the trade routes from New Spain (Mexico). Because of its striking cross-shaped flower arrangement (three petals swept forward and three forming a narrow tube), early European botanists noticed its resemblance to the cross of the Military Order of Santiago, or the Order of St James, giving it the names Jacobean lily and St James's lily. The genus name Sprekelia honours the German botanist Johann Heinrich von Spreckelsen. The species name formosissima is Latin for "most beautiful", which is hard to argue with.
Can sprekelia be grown outdoors in the UK?
Sprekelia can be grown outdoors in the UK during the summer months but must be brought inside before the first autumn frosts. The bulb is frost-tender and will be killed by temperatures below around 5 degrees Celsius. In practice this means treating sprekelia as a pot plant year round: move it outside to the warmest available spot in late spring or early summer once the risk of frost has passed, enjoy it through the summer, and return it under glass or indoors in September or October. Some gardeners in the very mildest parts of Cornwall, the Scilly Isles, or coastal west Wales may get away with leaving bulbs in the ground under a thick mulch through mild winters, but pot culture is far more reliable and allows you to control the baking and drying conditions the bulb needs.
What pests and diseases affect sprekelia?
As a member of the Amaryllidaceae family, sprekelia shares the same vulnerabilities as daffodils and hippeastrums. Narcissus bulb fly (Merodon equestris) can lay eggs near the base of the plant in summer; larvae tunnel into the bulb and cause wilting, distorted growth, or failure to emerge. Narcissus eelworm causes brown rings visible in a cross-section of the bulb and produces puckered, distorted foliage. Basal rot caused by Fusarium is the most common fungal problem, triggered by overwatering during dormancy. Vine weevil larvae are a risk for any pot-grown bulb; check for them when repotting. Red spider mite can colonise sprekelia grown under glass or on a dry, sunny windowsill in summer; the mite produces fine webbing and causes a dull, stippled appearance on the leaves.