Cultivation, Propagation

Meconopsis are not as widely grown as their attractiveness suggests they deserve. They have the reputation for being difficult, some certainly are, and some have proved, so far, impossible. But with understanding and knowledge, success with the more amenable ones should be possible, and to help in this way is the purpose of this part of our site.

Cultivation and propagation are described in four (linked) sections.

1. Cultivation: growing the plants in the garden
   
   
2. Vegetative (asexual) propagation
   
   
3. Raising from seed (by a number of knowledgeable contributors)
   
   
4. Diseases (under construction)

2. Vegetative (asexual) propagation by division (Evelyn Stevens)
For the big perennial blue poppies and other perennial species, propagation by division is an excellent way to increase a display of plants. A mature plant is lifted from the ground and carefully prized apart into a number of pieces. Each piece is then replanted and allowed to re-establish and develop into a new clump. It is the only way to propagate the sterile hybrids, which, of course, do not produce viable seed. Propagation by division has the disadvantage that the numbers that can be produced in a given year are far fewer than if from seed. A good yield for division of a mature clump might be as many as, say, 15 to 20 plants in one year, but usually many fewer. Each resulting plant should then be left to build up for several years before it can be divided again. A major benefit of propagation by division is that all the new young plants will be identical to the parent plant, i.e. they are clonal cultivars. This is particularly valuable in the case of the 'old', long-standing cultivars such as M. 'Slieve Donard'. When seeds are available, thousands of plants per year are possible from just a few fruit-capsules. Such plants will exhibit a range of variability, with the possibility that superior plants will result, but similarly, they may be less favourable in terms of flower quality or plant longevity.

Division is best carried out when the plant is in active growth, but when it is least likely to be stressed by environmental conditions. This means either early spring just as the new leaves are beginning to emerge or late summer into early autumn. If division is delayed until later in spring, the divisions will suffer greater stress due to water loss from the well-developed leaves, in the period before the roots broken by lifting have had time to become re-established. Once re-establishment has occurred, normal loss of water that occurs through the leaves is balanced by water uptake through the roots. In late summer, the plants are still in active growth and will re-establish if division is carried out then. Also fresh leaves will develop and there will be some build up of the plant, before the normal die back of late autumn. Whether division is carried out in spring or late summer/early autumn, it is obviously preferable to avoid periods of drought and to choose a time when the soil is moist from recent rainfall. If conditions become dry it is important to keep the plants well watered.

When a plant has matured over several years and become a sizeable clump, it can be carefully lifted and teased apart into several clumps and each replanted. It is preferable to use your hands for this teasinq apart, rather than slice through the clump with a spade. If you cannot manage the process with your hands, then careful insertion of a pair of forks, back-to-back into the clump, followed by pulling the forks apart from one another should provide sufficient gentle force to enable division.

A perennial plant (Infertile Blue Group) lifted from the ground in early spring.
Note the dead leaf bases on the soil surface and the soil intimately associated with the roots. The compact root-ball measured 20cm diameter by 20 cm deep.

Divisions of a perennial plant (Infertile Blue Group). The root-ball was prized apart to yield 7 divisions. For demonstration purposes the soil was washed off.
Note the development of new buds on each division.

If the maximum number of plants is required this can be achieved by carefully dividing a clump up into single shoots or buds, each with as much associated rhizome and adventitious root as possible (in the sample illustrated the soil has been largely washed off, this being for demonstration purposes only, of course). Each of these shoots or buds is a potential new plant. These small divisions are potted up in friable compost and kept under cover in the pots until a new root system has become well developed. It is possible that planting out into the garden straight away would be equally satisfactory, but I have never done this.

Maintaining health
It is well-known that the big perennial blue poppies can be very long-lived. Individual clumps are known to have persisted for many decades even if left undisturbed in one spot (e.g. the Ascreavie plant in the above illustration). But there is always the danger that a clump will deteriorate and dwindle away. Therefore to keep the plants in good health it is desirable or necessary to split them up in the way described above every few years and to replant the divisions a short distance apart from one another. This will overcome impoverishment of the soil and undesirable congestion of the new young shoots which develop in an established clump as it becomes ever larger in size. When dividing plants, opportunity should be taken to enrich the soil by adding garden compost and/or manure.

Rescue
If plants are not divided they will probably be seen to be deteriorating. Do not despair. It is usually perfectly possible to rescue such plants by digging them up, separating healthy shoots (even those with the most minimal amount of associated root system are likely to re-establish) and repotting them individually into good compost. Then keep an eye on them under cover until they have re-established. I have done this on a number of occasions, but do not have experience of merely replanting such ailing plants into the open garden - it might be successful: re-potting certainly is.

Disbudding
Some growers maintain that it is vital to prevent a new plant from flowering in its first year by removing the flowering shoot should one develop. My own experience is that this is not necessary, although possibly preferable. In order to test the disbudding theory, on many occasions I have allowed a new plant to produce its one and only flower, and then found that side-shoots are nearly always (on over 90% of occasions) formed. These then develop into a satisfactory plant by the next year and into a good clump by the following year.

Further information on vegetative propagation will be found in the following Genus sections:

3. Variability and supplementary page Perennial Meconopsis for a discussion of the perennial habit (living and flowering for many years).

4. Big perennial blue poppies and supplementary page Longevity (for comments on longevity in M. 'Lingholm' and M. betonicifolia).

This is the end of Section 2; for other sections of Cultivation, Propagation click on one of the links:

1. Cultivation: growing the plants in the garden
2. Vegetative (asexual) propagation

3. Raising from seed
4. Diseases (under construction)