Cultivation

Cultivation and propagation are described in four  sections.

1. Cultivation: growing the plants in the garden
2. Vegetative (asexual) propagation
3. Raising from seed 
4. Diseases 

Raising From Seed

by Ian Christie (Christie’s Nursery, Angus, East Scotland)

Seed harvesting and storage  The fruit-capsules should be harvested when they are ripe and begin to open up. They should then be left in an airy cool place to dry completely when all the seed can be shaken out of the capsules. The good seeds should be separated from any debris and improperly developed seeds, and kept in paper envelopes in a plastic box in the fridge or in a freezer.

Seed sowing, germination, pricking out and potting on

Composts for seed sowing  Mix one part John Innes ( No2 or No3 ) soil based compost with one part peat-based compost and one part sharp grit or perlite/vermiculite, fill pots or tray with compost and water well.

Seed sowing  When you have your own seed, sow some as soon as it is ripe. Then store the rest, labelled clearly, in a small container in a household fridge. We then sow some more seed just after New Year.

In warmer climates, in areas which do not get any frost, place some seed mixed with slightly damp grit or perlite inside a polythene bag, tie the bag securely and place in a household freezer for a day or two, then remove and follow the above methods.

Seeds can be sown in Scotland as late as March or even into late April with success and for at least one expert grower, early March is the preferred option.

For seeds from your own plants or from some other source, place the seed in a shallow saucer or on paper, add a small amount of fungicide to the seed mix thus coating the seed well with the white powdered fungicide, sow seed on the surface of the pot or tray, carefully and not too densely. You can readily see how densely you have sown the seeds when they are coated with the white powder. Place the pots or trays outside. It is best to put some netting over them to protect from birds, cats etc. Once the seedlings germinate around the end of February or early March, we bring a few pots into a cold glasshouse. This enables the seedlings to grow more quickly. Great care must be taken with watering at this stage as there is a real likelihood of seedlings damping off if given too much water.

Pricking out  

Seedlings can be pricked out or thinned out at an early stage. But it is maybe prudent to leave half your seedlings undisturbed at this stage, so that if you fail with the first batch you can try again. Seedlings can be pricked out into trays or large pots depending on how many plants you need. Once pricked out, place seedlings in a frame or other covered area. Make sure to shade seedlings from strong sunlight. As the seedlings grow, a liquid feed with diluted fertiliser will help strong growth. Also spray with fungicide if there are any signs of damping off. This is best done in the evening when it is cooler but be careful to use only the recommended strength as seedlings will burn when fungicide spray is used excessively.

Potting on  

When the plants begin to become congested in the trays or pots they can be potted on individually into pots. Then, if sufficiently large, they can be planted out into the garden in late summer or early autumn. Alternatively, they can be kept in pots under cover in a cold greenhouse or frame over winter for planting out the following spring.

A special case: M. punicea  It seems to be generally agreed that it is important to sow the seed of M. punicea as soon as it is ripe, or as soon after as possible. Success is much less assured for seed sown 6 months or so after ripening. The seed should be subjected to a period of below zero temperatures.

by James Cobb (East Scotland)

I garden in the East Neuk of Fife in the east of Scotland where the rainfall is as low as anywhere in the UK. While it is not often above 25C, the air can be very dry and there is always a risk of small levels of salt spray. The soil is very free-draining, contains lime and needs organic matter constantly replaced. This is certainly not an ideal place to grow Meconopsis but as they are so easy from seed, which is normally set in abundance, it does not present any insuperable difficulties. I do find it much more difficult to maintain named clones that need vegetative propagation in the last ten years and indeed now regularly renew all the ‘Big Blue Poppies’ from seed. Snow cover is very rare but even in hard frosts most plants over-winter without protection – probably because they are on the dry side

The seeds

For many of the commonly available species, they are not a difficult group of plants. There are four types of Meconopsis that can be grown from seed. Perennial plants that are deciduous (like M. baileyi); plants that are deciduous and flower as biennials and then die (like M. horridula); plants that are evergreen and flower as biennials (like M. wallichii) and plants that are evergreen and die after flowering maybe 3 or 4 years later but meantime have lovely winter rosettes (like M. napaulensis hybrids). If you don’t have your own supply of seed then the various seed exchanges are much better than commercial sources since the latter are usually a year older. Most plants set very generous amounts of seed so there is usually a big surplus in the seed exchanges. One problem with seed exchanges (but professional sources are guilty too) is that what is offered may not be true to type. As you become more interested in this group of plants you will be able to identify them more reliably but also, hopefully, meet with like enthusiasts who will exchange seed. Meconopsis seed is generally fairly long-lived and should be stored dry (over silica gel) in the bottom of a fridge if for more than a few months. Seed from the current year’s harvest is quite safe stored cool and dry (in the coldest room in a house) until it is sown in the New Year. It is possible to sow seed that is freshly harvested. Some nurserymen in the past have done this to obtain larger plants for sale the following year. It is however not to be recommended as small seedlings tend to over-winter badly and for the amateur there are really no advantages.

My method

What follows is my personal recipe developed from 30 odd years’ experience. This produces very good plants by early summer. Seed is sown into a sterile compost in mid January. Peat-based compost is probably best and it should not be heavily pressed down. If you wish to use an alternative to peat make sure it is a very light open compost. There is nothing magic about the seed compost and a John Innes type is as good. I used to add sieved leaf mould but am a little wary of this in case it introduces fungal pathogens. Meconopsis seed has quite good food reserves in it and seedlings grow away rapidly if happy. It is imperative that you sow the seed thinly. The seed needs a covering of about 2-3 mm of compost on top. If you need a lot of plants then use a big tray and if you are worried about the quality of the seed you still must not sow it too thickly just in case it does all come. I leave the seed pots (watered from below) in the cold under glass for about 3 weeks and then apply heat underneath from warming cables with a thermostat setting of about 15C. The seed pots are left in full light and if they need watering at this stage it is better done from below in order to avoid washing the seed together into clumps. Germination is usually quite rapid (it can vary by 3 weeks between different seed batches). If germination does not occur in about 6 weeks it probably wont! With rare seed and with M. punicea it is worth saving the pots for a second year.

As soon as the first sign of the true leaves are seen they need to be pricked on. This should be into a nice rich but light compost. I use ¼ peat based compost, ¼ John Innes No 2, ¼ leafmould and ¼ course grit. I add something like Vitax Q4 as well as an appropriate amount of slow release granules in the peat-based compost. Again they are not fussy but the compost does need good nutrient levels and needs to stay open and airy. Seedlings are probably not fussy about lime but generally I only use dolomitic limestone in my Meconopsis composts. Small quantities of ordinary limestone may even be quite valuable but I would not use large quantities of this.

I prick on 60 to 70 seedlings in a standard tray and keep them growing on under cold glass. As soon as they are beginning to touch in the tray then they are potted on into to single pots in the same rich but light and airy compost with good levels of added inorganic nutrients as well as leaf mould. They prefer a site with two or three hours a day of sun. In southern parts of the U.K. and hotter parts of the world they may need total light shade. A net covered tunnel makes an excellent site to grow them. They do not like drying winds at this stage since the leaves can be burnt. It is also critical to keep them watered – it is probably difficult at this stage to overwater them. The most difficult thing to maintain in a hot dry summer is high ambient levels of humidity. This does not matter in the early stages since they are very robust then. As summer turns to autumn a lack of humidity may induce mildew and this can lead to losses. The best way of maintaining humidity for a modest collection of Meconopsis seedlings is to place them in a tray surrounded by moss (preferably sphagnum) which itself is permanently dipped in water and acting as a wick.

Some species like M. horridula, aculeata and the evergreen wallichii will flower as biennials. These need growing on fast and planting out into a rich garden soil as soon as they fill the pots or potting on into larger ones. This also applies to M. punicea – the bigger you can get a plant by the end of the first years growing season then the better that it will flower the next year. When planting out Meconopsis they like deeply dug and well manured ground and the better you do it the greater will be your reward. The species like M. napaulensis and M. superba that are monocarpic, but take several years to flower, can become quite pot bound and even be over-wintered the first year in small pots and will then grow away strongly when planted to rich ground. The one problem with this group of plants in pots is that overhead watering needs to be done with some care or all the water is just shed off the plant by the leaves outside the pot! Species that are potentially perennial like Meconopsis (Fertile Blue Group) ‘Lingholm’ and M. baileyi need the same rich treatment and growing on fast. The bigger they are when they go dormant in autumn the more likely they are to flower the next year and have the strength to make new vegetative shoots and become perennial. It should be remembered that some strains of M. grandis, M baileyi and certain hybrids have an innate tendency to die after first flowering. I would NOT take flower buds out in the first year. If a plant ‘wants’ to be perennial and is well grown in rich soil it is quite capable of flowering, setting seed and developing into a multi-crowned plant. At least like this you will have some seed if it dies after flowering. To my knowledge only M. superba sets seed if you have a single plant – so always aim for several. As a genus they are wicked at hybridising so a collection of different species will not remain true for long.

Special cases

The purple flowered species from China like M. lancifolia and including the highly desirable M. delavayi are definitely much more difficult. They germinate easily enough using the above scheme and may grow on well, if less vigorously. By early August a fungal infection sets in that blackens the leaf petioles which eventually spreads to the crown. At one time I did not advocate chemicals (one still needs care with insecticides against aphids which can be a nuisance and a dilute non systemic one is best) but I have found dilute fungicide will keep this fungus at bay and I now can keep M. delavayi going to flowering. This problem will be worse the drier your climate, and the wet moss tray around the plants in full shade will help. The fungicide I use is Octave but it is not available to amateurs. I have also used Benlate and even the potato blight fungicide Maneb. I use all of them very dilute (at least 1/5th strength) and will apply daily if necessary to real treasures and run the stuff into the tiny crowns with a paint brush. I used to have the same problem with M. sherriffi and if I ever get the chance with this again I shall use a dilute fungicide from quite early on.

Advice for beginners

If you are a beginner, then with species like M. horridula, M. napaulensis and even the blue poppies like M. ‘Lingholm’ and M. baileyi, they are no more difficult to grow than most garden annuals. Seed sown without artificial heat will still produce good plants when it naturally germinates in April. The ultimate secret with Meconopsis is really rich feeding in a deeply dug soil.

Notes on Raising from Seed

by Leslie Drummond  (East Scotland)

I use J. Innes type compost – a mix of garden soil, peat and sharp sand with the addition of a little sieved, well-rotted garden compost to ensure that it is rich in live bacteria etc.

If fresh seed is available, sow half fresh and half in Nov/Dec in small plastic pots. Cover thinly with 1-3mm grit, water well and stand outside in shade in a box which can be covered with glass in heavy rain.

Never allow to dry out: beware of slugs and blackbirds; examine regularly and remove moss and liverwort as it appears.

As germination occurs (usually Feb to April) move the pots to a shady alpine house. A little extra grit can help ‘floating’ seeds to root. If necessary, thin to 5-10mm spacing to minimise damping off – treat with a very dilute fungicide at the first signs of this.

Prick out seedlings as the first leaves develop, using the same compost in plastic pots, and grow on in a sheltered shady spot.

by Bill Terry (Sechelt, near Vancouver, British Columbia, Canada)

I live by the sea in the Pacific North West, a short distance up the coast from Vancouver. The climate is equable. USDA hardiness Zone 8. A range of temperatures comparable to Southern England. Only in this corner of Canada are we spared the extremes endured in the rest of the country.

Winter temperatures normally range from 2 to 8° C. Frost is uncommon, spring frosts from mid March unheard of. (Spring starts early here. By the end of January the new leaves of perennial Meconopsis start to appear). Snow is rare. Summer highs are generally in the low twenties, up to 25° C. Afternoon sun can be hard on Meconopsis, so I plant in part shade, preferably deciduous shade. Rain distribution is uneven, with dry summers and very wet winters. Annual rainfall averages 1.2 metres, 85% falling between October and March. There are exceptions: weeks of drought in summer and (a challenge for the Himalayan Poppy grower) winter deluges like January 2005 (450mm in the month).

Most authorities suggest starting Meconopsis seed in fall. I have tried this and found that loss of seedlings due to winter wet, even when sheltered overhead, cancels the advantages of high germination. Provided seed is stored in the frig, in any container that keeps it dry, satisfactory germination can be expected from winter or spring sowing. So I start seeds at the end of January, indoors under lights in a cool back room. Conditions can be controlled exactly – light, heat, moisture. The ambient room temperature falls to 13° C at night, when the lights are off, and reaches 20° C by day with the lights on – for 12 hours. Fluorescent lights do generate a little warmth, so the surface temperature of the seed bed reaches about 23° C. I do not use bottom heat. Ordinary fluorescent tubes are fine. In my experience, the expensive grow lights make no difference. I believe this operation could be set up equally well in a cool, shaded greenhouse, with thermostat set to about 11° Celsius.

Growing medium   

Any sterile, peat based or loam based compost. I use the equivalent of Fison’s or John Innes No.1 and to this add roughly 25% by volume of grit (coarse sand and perlite) for optimum drainage. I add no fertiliser or fungicide.

Containers   

I start seed in the small six cell plastic containers commonly used by nurseries selling annuals. I re-use these year after year, washing them each time in a mild bleach solution. Once sown, containers are placed under lights on a shallow layer of perlite so that excess water does not accumulate in or around the base. The lights are hung 2-3 inches from the surface.

Sowing   

Compost should be moist, so that a handful squeezed will tend to hold together but not drip. Containers are filled to the top, gently tamped down, but not compressed. . Seed is thinly scattered on the surface (roughly 8-10 seeds per cell) and gently pressed with a finger for proper contact. Then I scatter a very thin layer of fine vermiculite. This should not shut out light but will help keep the surface damp.

Watering  

The seeds are sprayed using a simple hand pumped plastic sprayer, when planted and thereafter morning and evening, or as required – check the weight of the containers to see if there’s adequate moisture. I have never had a ‘damp-off’ problem. If I feared that, I would probably add a very dilute dose of fungicide to the water. The water is tap water at room temp, left to stand for a day to lose chlorine.

Germination   

This should happen in 2-4 weeks. Seedlings may be thinned with tweezers to 4-5 per cell. After germination I move the seedlings to a cool (frost free) conservatory. Or, if the danger of frost is past, to a cold frame. They could just as well stay under the lights, but I need the space. Potting on   After the seedlings have been hardened off, I pop them singly into 4 (10cm) plastic pots. This happens between 2-3 months from sowing, when the seedlings, still tiny, have two true leaves. Same compost mix as before. In transplanting, I tip out the cell and carefully separate the plants handling them by a leaf. They should easily come apart, with no root damage, if the mix is moist but not wet and if the transplant is done before roots become tangled. A pot is filled loosely to the brim with compost; I make a deep hole with a finger and, holding the plant by a leaf, lower it into the hole while firming the compost around and adding a bit more as needed. The seedling must be planted at exactly the same depth as before, with the compost surface about 1/2in from the top of the pot. I water in with half strength ‘plant starter’ – or any soluble fertiliser with a high middle number (i.e. high in phosphorus, P). I also sprinkle a pinch of slow release fertiliser on the surface. If carefully handled perennial big blue poppies transplant easily at this stage. My survival rate is better than 95%.

Growing on   

The seedlings grow on outside in the shade, on a table with a wire mesh top. If slugs are a threat, the table legs can be banded with ‘tanglefoot’. All that’s needed thereafter is regular watering and (here) occasional ridding of liverwort by prizing it out and topping up with compost if needed. The plants should be ready for planting out by August.

These methods work well for me for starting all available species, perennial and monocarpic. Exceptions are M. superba – which I believe is better started in a cold frame in fall, because seed seems very short lived – and MM punicea and quintuplinervia, which appear to need frost to break dormancy.