How to grow Doodia
Also known as the hacksaw fern or rasp fern, doodia is an evergreen fern found in damp, woodland margins in Australasia. In appearance it is similar to polypodium and blechnum (being closely related to the latter), though it has the added feature of its fronds being brightly coloured when young. Usually, these are pink, though in the case of the ‘Rough Ruby’ cultivar they emerge orange and red.
Doodia is a half-hardy fern which will need protection from hard frosts. Alternatively, it may be grown as a conservatory or greenhouse plant.
Zantedeschia is a genus of flowering plants from the family Araceae and is native to southern Africa. With a rich history dating back to the Ancient Romans, these deciduous or semi-evergreen perennials have been used as a symbol of celebration. Zantedeschia was Named after Professor Giovanni Zantedeschia, an Italian botanist.
There are two main forms of Zantedeschia: hardy and tender. Hardy forms of the plant can be grown outdoors, enjoy moist soil and full sun or partially shaded conditions - these are known as Arum lilies. Tender forms of Zantedeschia prefer being grown in containers or pots and should be brought inside over the winter - these are known as Calla lilies.
With tuberous flora in all colours from whites, yellows and oranges to deep reds and purples, Zantedeschias are not to be overlooked in any garden, as long as they have sufficient sunlight to grow in.
Ready to learn more about growing Zantedeschia? Read on for all there is to know...
Key Information
Soil pH
Position
Hardiness
Where & when to plant Doodia
Position - Outdoors: a sheltered, partially shaded spot
Indoors: bright, filtered light in summer, moving to full light in winter.
Soil - Reliably moist yet not waterlogged, with a neutral to acidic pH
Compost - Ideally, mix your own potting compost following this gold standard recipe for acid-loving ferns:
1 part each of loam, charcoal, and medium grade bark
2 parts sharp sand
3 parts coarse leaf mould.
Alternatively, use a good quality ericacous compost with added sharp sand or grit.
Hardiness - Half-hardy, rated H3 (1 to -5°C)
Doodia grows naturally in a warm, frost-free climate, and can only survive outside in the UK once risk of frost has passed. This varies from region to region, though tends to be mid to late May. If your plant arrives before it is safe to move it out, keep it in a protected environment such as a conservatory, greenhouse, or a sunny windowsill or porch until the time is right.
Gardeners in the milder, southern half of the UK or with a warm microclimate (perhaps in a coastal or urban location) may get away with growing doodia in the open ground in a warm, sheltered spot, with protective measures taken during winter (see ‘Cold Protection’). The base of a wall, edge of a stream or pond, or woodland garden are all ideal. Just ensure the spot gets more shade than sun and isn’t prone to drying out during summer.
In chillier spots and further north, it is best to grow this fern in a container to allow for overwintering indoors. It can even be kept indoors all year round as a permanent conservatory or greenhouse plant, where it will need plenty of brightness though no direct light during the summer months.
Any planting, potting, or repotting is best done in spring.
How to plant Doodia
· For planting in the garden, dig the soil area removing any large stones and weeds and breaking up any lumps. Rake level and firm with your heels. Rake level again. Now is the time to add well-rotted organic matter – something acidic like leaf mould, decomposed pine needles, or an ericaceous soil improver is ideal.
· Water your doodia well and allow it to drain before planting.
· Dig a hole twice the width of the root-ball.
· Place the plant in the hole, ensuring the top of the root ball sits level with the surface of the soil. Too low and the plant may rot, too high and the roots can dry out.
· Backfill with soil and firm in gently with your foot.
· Soak well with water.
· Mulch around the base with the well-rotted organic matter mentioned above.
· For planting in a container first choose an appropriately sized pot. Doodia is a slowly spreading, creeping plant so does best in an individual rather than mixed container. The best practice is to choose one just a few centimetres larger than the current rootball and increase every year or two. Always ensure there are plenty of drainage holes in the bottom.
· Using either of the potting composts suggested above, start by partially filling the pot with compost; enough so that when placed on it the upper surface of the root ball is about 3 centimetres lower than the top of the pot.
· Fill around the plant with compost, firming down with your fingers then adding a little more so it is held tight.
· Pick up the container and lightly tap on the potting bench or ground a few times to help further settle the compost around the plant.
· Soak well with water.
· A mulch with horticultural grit will look attractive and help to prevent a ‘cap’ or crust forming on the top of the compost (something container plants can suffer due to the artificial nature of their watering).
What to plant with Doodia
If you have the moist, shady, acidic conditions needed to grow doodia, other plants which will also thrive include trillium, liriope, meconopsis, Japanese anemone, and leucothoe, as well as other ferns such as blechnum and polystichum.
Alternatively, if keeping your doodia as a conservatory or greenhouse plant, companions with similar growing requirements may include adiantum, colocasia, solenostemon, and cyrtomium.
How to care for Doodia
Pruning and Deadheading
Cut away any tatty, faded fronds in spring just as new growth emerges. It is fine to cut off all fronds if necessary.
Watering
Doodia enjoys moist conditions and so, when grown outside, benefits from a good watering in on planting and then regular soakings until established. After this and providing it is grown in the right conditions with an annual mulch (more on this next), it should need watering only in prolonged periods of hot, dry weather.
Grown in a container, doodia can be watered freely throughout the growing season (roughly March to September), aiming for consistently moist but not soggy compost. Be aware that in hot weather, containers may need watering more often than you might think (particularly smaller containers or those kept indoors). The odd squirt from a misting bottle is a good idea for those residing permanently inside, as this is a plant which enjoys moderate humidity levels. As growth slows in autumn reduce watering to the bare minimum, i.e., just enough to prevent the compost drying out completely.
Feeding
On healthy, fertile soil, a mulch of well-rotted organic matter should provide enough nutrients for your doodia. Something acidic like leaf mould, decomposed pine needles, or an ericaceous soil improver is ideal, though manure or garden compost will also do fine.
As well as feeding the soil, mulch has the added benefit of suppressing weeds and locking in moisture. Do so when planting, and then again each spring.
If you garden on poor soil or your doodia looks in need of a boost, applying a granular feed (again, ericaceous if you have it, general purpose if not) to the surface of the soil and lightly working in can reap benefits. This is known as a top dress and should be done when you’re mulching in spring – first apply the feed, then cover with the mulch.
Container-grown plants rely more on the gardener for nutrition. Start by making sure you use a good quality ericaceous compost (suggestions above), then from March to the end of July apply an ericaceous liquid feed at regular intervals according to the manufacturer instructions.
Remember also to repot your doodia every few years, going up slightly in pot size and using fresh compost. Once the plant reaches full size an annual top dress is advisable: each spring, scrape off the top 5 centimetres of compost and replace with fresh.
Cold Protection
Where winters remain relatively mild, doodia can be grown outdoors in a sheltered spot and covered with a protective mulch of straw or layer of horticultural fleece over winter.
Otherwise, it is best grown a container so that it can be overwintered indoors in a cool yet frost-free environment. A conservatory, greenhouse, or porch are all perfect spots.
Pests and Diseases
Doodia is considered trouble-free.
How to propagate Doodia
Established doodia plants will produce offsets (new plants) around their base, and the quickest and easiest method of propagation is simply teasing these away from the parent and potting up into individual containers. Grow on in a warm, protected environment, giving just enough moisture to prevent drying out completely – too much at this stage is likely to encourage fungal problems.
Once established, pot up or plant as above.
* Many plants carry Plant Breeders Rights and cannot be propagated for commercial purposes.
Common Doodia Questions
· Is doodia poisonous?
Doodia has no reported toxic effects on people or animals.
· Why is doodia known as rasp fern?
Its fronds have a coarse, sandpapery feel to the touch. This acts as a deterrent against grazing animals such as rabbits or deer, making it a good choice for rural gardens.
