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YOUR GARDENING QUESTIONS THIS MONTH

Your questions answered.

QDIY SAFFRON Can the stamens of any crocus variety be dried and used as saffron? If not, are real saffron bulbs available in New Zealand.

I’d love to grow my own as it is so expensive.

KIM PERRY, NAPIER

AIt would be great if you could harvest saffron from any crocus, but sadly, no, this spice only comes from the autumn-flowering species, Crocus sativus.

It is the red stigma, not the yellow stamens, that are dried and used to colour and flavour food.

Saffron is expensive because it is so labour intensive to harvest. Each flower has only three stigma and it takes around 300 of them to make one gram. Each flower has to be picked individually and the stigma have to be separated from the petals by hand. That's a lot of flowers to pick and process! The good news is that saffron does grow in New Zealand. Only tiny amounts – a thread or two – are needed per recipe so it's possible to grow a supply for home use.

Saffron corms lie dormant for long periods so it's easy to accidentally dig them up or lose them in the garden. For this reason, it's a good idea to grow them in their own dedicated pot.

Plant the corms in early summer in rich, well-drained soil 5-10cm apart and 15cm deep. Fertilise with a specific bulb fertiliser at planting and again in January or February. Don't overdo nitrogen fertilisers which will encourage leaves at the expense of flowers. Grow in full sun and water when the leaves appear.

Flowering is from late March to early May depending on the season. Each corm produces several blooms over a four-week period.

The flowers deteriorate quickly so need to be picked as early as possible on the day they open. Once removed from the petals, the stigma are dried in a dehydrator (for small quantities, on a sunny windowsill). Store in an airtight container.

After flowering, keep watering and feed regularly with a liquid fertiliser as now's the time the energy to produce next year's flowers is being stored.

The corms are propagated by division. Dig them up every two to three years to divide and expand your saffron patch. Saffron corms sell out quickly and are usually ordered in advance in anticipation of delivery in time for planting in December. Order from Oderings (oderings.co.nz), Kiwi Saffron (kiwisaffron.com), Wild About Saffron (wildaboutsaffronco.nz) or Bulbs Direct (bulbsdirect.co.nz). Barbara Smith

QMYSTERY BULB We found these bulbs growing above ground in Palmerston North. We planted one and it worked its way up until it sat on top of the ground. Can you shed any light on this?

WENDY MAJOOR & MANDY MCKAY, PALMERSTON NORTH

AWe consulted specialist bulb grower, Tony Palmer, from Kellydale Nursery in Oratia, West Auckland and Bulbs & Perennials Society member Cherie Buckingham. Without a flower to confirm the identification, they think it could well be an immature Albuca nelsonii bulb.

Albuca bulbs grow partially above the surface and get very big. A flower would confirm it so do send a picture when it blooms.

Albuca nelsonii flowers are white and usually have a green stripe. They are carried on upright stems about 1.2m tall and appear in spring and early summer. Plants need good drainage and partial shade.

Bulbs moving up (or down) through the soil isn’t uncommon. We think of bulbs staying put but they do have some ability to manoeuvre themselves into their preferred growing position.

Some bulbs have contractile roots that pull themselves to their preferred depth which may vary depending on the soil density. Bulbs have been found to react to sunlight penetrating the soil (specifically the blue end of the spectrum). Bulbs that are least tolerant of exposure to blue rays will bury themselves more deeply.

Bulbs planted upside down will right themselves eventually and those left on the surface can bury themselves in a year or two.

Barbara Smith

QWHAT’S MY NAME? This gorgeous unknown plant from the Marlborough Sounds was given to me in February 2019. It is 25cm in height and has never stopped flowering. Can you identify it for me?

ADRIENNE PRESTON, CHRISTCHURCH

AOur Christchurch regional writer Mary Lovell-Smith identified your plant as alonsoa. The five-petalled blooms are said to resemble carnival masks, giving rise to the common name mask flower. There are apricot, pink and orange forms too.

It’s a very pretty, short-lived perennial that can also be grown as an annual by sowing seed in autumn or spring.

Plants can also be propagated by cuttings or by layering the stems.

Alonsoa prefers a sunny place with well-drained soil enriched with compost and fertiliser.

Originally from tropical Central America, alonsoa can only cope with very light frosts. Protect plants over winter in colder areas. Autumn-sown seedlings should be kept under shelter during winter.

Pinch out the growing tips to keep plants compact and encourage more flowers. They are pretty trouble free and not prone to disease, but watch out for aphids.

It is a shame that alonsoa are not more widely available as they are easy-care, cheerful plants that flower for most of the year. Look out for them on garden club trading tables and independent garden centres where they grow their own seedlings.

Seeds are available via Trade Me from Rolleston-based Seeds4U. Barbara Smith