Increasing your Violas and Violettas

Table of Contents and IntroductionAfrican Violets: the Doyen of House PlantsAgapanthusAlstroemeriasAmerican SagebrushesAmerican WildflowersAndean Nymph - a pink mimulusAquilegias (Columbines)AuriculasAustralian AnnualsBellis Perennis (Daisies)Black-Eyed SusanBlue African LiliesBreeding DelphiniumsBreeding Fuchsias: Part 1: From SeedBreeding Fuchsias: Part 2: HybridisationBromeliads from SeedButterflies in Soy SauceCacti RaisingCampanulasChilean Bell FlowerChilly Treatment for Peruvian LiliesCollecting SeedConserving Annuals and BiennialsCosmosCucumbersCycads: Living FossilsCyclamen for IndoorsDahlias from SeedDamping OffErythroniumsF1 Hybrid - What Is it?F2 and Open Pollinated VarietiesFrom Obscurity to the Height of FashionGentiansGeraniumsGermination to Pricking OutGolden Impatiens - The StoryGrowing Alpines From Seed: Part 1Growing Alpines From Seed: Part 2Growing Bananas From SeedGrowing Cyclamen From SeedGrowing Eucalyptus From SeedGrowing Ferns from SporesGrowing Foxgloves From SeedGrowing Fritillarias From SeedGrowing From Seed: From Packet to SoilGrowing Hardy Ferns from SporesGrowing Hardy Geraniums From SeedGrowing Lewisias From SeedGrowing Magnolias From SeedGrowing Meconopsis From SeedGrowing Proteas and Related Genera from SeedHandling Small SeedsHardy Annuals: Part 1Hardy Annuals: Part 2Hardy CyclamenHardy SpurgesHelleboresIncreasing your Violas and ViolettasKeeping Records of Seed SowingLettuce - the Vital Part of any SaladLord Anson's PeaMagnolias - the Root of the ProblemMimulus from Seed to Seed in Sixty DaysNew Guinea ImpatiensOld-fashioned Sweet PeasOnions with EverythingPansies are not Difficult to Grow from SeedParsleyPerennials for American GardensPetuniasPhygelius - their cultivation and propagationPinks: Evocation of the PastPlants That Flower OncePrickly but NicePropagatorsRadishesRaising PalmsRaising PrimulasSalad Leaves - a lot to be desiredShow Stoppers Twice OverSowing SeedsSowing in Open GroundSowing to Feed our FriendsSturt's Desert PeaSweet Peas - Autumn SownSweet Peas - Sowing and GerminatingTall and HandsomeTechniques with Tiny SeedTexas BluebellThe Effect of Light on Germination and SeedlingsThe Nervous PeaThe Scarlet Welsh PoppyThe Search for the Yellow Sweet PeaToad LiliesTomatoesTreasure Hunt for TasteUnderstanding Latin NamesUnique Poppy (Mother of Pearl)Viability of VegetablesWeaning SeedlingsWill the Real Mimosa Please Stand Up

Rodney Fuller discusses the various methods of propagating these colourful plants.

In common with many of the herbaceous plants of the garden there is more than one method by which it is possible to increase a stock of violas and violettas, none of which demands exceptional skill or particularly sophisticated equipment. The method chosen for the propagation will depend to some extent upon the physical characteristics of a particular variety and the quantity of plants which is ultimately required.

The object of the exercise may be to do no more than rejuvenate a variety which, due to the passage of time, is exhibiting loss of vigour, in which case it will be satisfactory if the result is another healthy and vigorous replacement plant. Alternatively the object may be to produce the dramatic effect of mass planting of a particular variety and the challenge will be to attempt to produce the maximum number of healthy, vigorous, new plants from each single stock plant. The ability to achieve this will, to a very large extent, depend upon the physical characteristics of the chosen stock plant and the manner in which it has been cultivated.

The basic methods which can be applied to the propagation of violas and violettas are: division, cutting and seeds. The dividing line between a small division and a cutting are somewhat blurred, as will be explained in greater detail later.

To the experienced eye, no two varieties of viola or violetta exhibit precisely the same physical characteristics of growth and although the differences may appear slight they may well be sufficient to influence the technique employed for propagation.

Divisions

The division of a healthy, mature plant into a number of smaller portions, each with an adequate share of the overall root system is undoubtedly the most basic and simple form of propagation but it is a method which is only possible if the habit of growth of a particular variety makes satisfactory division practical.

A viola or violetta with what is termed 'tufted' habit will have a vigorous, spreading root system from which new, young basal shoots will sprout in such profusion that a mature plant may well consist of as many as fifty such shoots. If the plant is carefully lifted in its entirety from the soil it should be comparatively easy to divide the plant into a number of separate portions, each with its adequate share of the active root system and if these are transplanted into fresh soil elsewhere, and watered in, they should grow away in a virtually uninterrupted fashion. If only a few plants are required the divisions can be quite large with a number of healthy, new basal shoots on each and such divisions should re-establish readily. When a greater number of plants is the requirement these large divisions can be sub-divided still further to give an increased quantity of what would consequently be smaller divisions with fewer shoots and a correspondingly smaller share of the root system. These smaller divisions would be rather more delicate and vulnerable until established but with adequate care should rapidly form vigorous new plants.

It is important that all divisions should appear to be in sound health and have adequate young root development. Any old, spent top growth or decaying root should be carefully trimmed away before the divisions are transplanted into fresh soil and any attempt to divide a plant into too many very small portions is not recommended.

A true violetta will have the compact, tufted habit of growth which will render division of the plant comparatively easy. Violas of tufted habit will be equally suitable candidates for division. There are however many viola varieties with a rather more straggling and pansy-like habit of growth. The top growth of these varieties will be largely supported by a single base stem at ground level with the inevitable result that division in the aforementioned manner will not be possible and alternative methods of propagation will have to be considered. The species Viola cornuta and its many garden varieties have a rather different habit of growth which makes a form of division particularly easy. A mature plant of a V. cornuta variety will produce a mass of what might best be described as stolons or underground shoots which emanate from the crown of the plant and terminate with a new shoot above soil level. If these growths are left undisturbed for a matter of weeks they will form fresh roots and can then be detached from the parent plant and transferred to fresh soil elsewhere. Cornuta varieties of viola are particularly easier to multiply in this manner.

All forms of division should be planted to at least the depth to which they were previously growing, preferably a little deeper, and watered well in order to consolidate the new soil around their roots until they have fully established.

Cuttings

Propagation by means of cuttings, whilst being a somewhat more complex operation than division, is undoubtedly the most satisfactory method to employ when the intention is to multiply stocks of violas and violettas in greater quantity.

A cutting is a healthy shoot which is detached from the parent plant and then treated in such a manner as to encourage it to form a root system and become an individual, self-supporting plant. If the intention is to propagate violas and violettas by way of cuttings it is important to cultivate the parent plants in such a way as to encourage the formation of an adequate supply of healthy, stocky, non-flowering basal shoots as it is these growths which will undoubtedly provide the most suitable material for cuttings.

If a viola or violetta is left entirely to its own devices much of its energy will go into the production of flowers and subsequently seed. If, however, during the latter weeks of summer, the mature, flowering stalks of the plant are trimmed back to within 2.5-5cm (1-2in) of the soil level the plant's energy will be diverted into the production of new basal shoots which can then be detached from the plant and used as cuttings before they themselves have reached the stage of producing flower buds. Whilst it is an unpleasant task to butcher the plant whilst it is in full flower, if the ultimate result is to be perhaps as many as fifty fresh young plants for flowering the following season the loss becomes easy to bear.

Within a few weeks of trimming the chosen stock plant, provided that the plant has received adequate moisture and nutrition, it should be bristling with basal shoots 2.5-5cm (1-2in) in height and preparation of cuttings can then begin. The shoots should be severed at or beneath ground level with a clean sharp knife or alternatively if the whole plant is lifted from the soil, the basal shoots can be separated from the parent plant by carefully pulling them in a downward and outward direction.

If the plant has been top dressed with fine soil or compost at the time of pruning it will be not unusual to find that a number of the basal shoots are already forming rudimentary roots. Any shoots that show no evidence of root should have the lowest leaves removed and be trimmed directly beneath the lowest leaf joint. Any shoots which emanate from beneath soil level will have a blanched and leafless base and will require no further attention.

As a precautionary measure the cuttings can be dipped into hormone rooting powder. The cuttings are now ready for insertion into a fine, free-draining, but moisture-retentive, compost and for placing in an environment in which humidity can be maintained until such time as rooting has taken place and the cuttings have become self-supporting. Cuttings can be housed in a simple structure which provides protection from severe weather and scorching sun whilst allowing for adequate natural lighting and ventilation. There is no necessity for artificial heating. The cuttings should be inspected at regular intervals to ensure that the moisture content of the compost is sufficient to prevent flagging. Excessive humidity and the stagnant air may well encourage fungal rot. Adequate ventilation should help to deter this. If slugs, snails or other predatory creatures appear to threaten the cuttings, steps can be taken to discourage them. Autumn cuttings should be well rooted by spring and therefore ready for planting out into their final quarters in April or May depending upon the condition of the weather and soil.

Whilst harvesting cutting material it is not unusual to find basal shoots with quite well developed young root systems, and young lateral shoots whose close proximity with the moist soil has induced them to have already formed rudimentary aerial roots. Both of these types of shoot will form ideal material for propagation purposes but it would be misleading to refer to them as either cuttings or divisions - the traditional expression 'Irishman's cuttings' being perhaps more appropriate. Violas of less tufted and more straggly, pansy-like habit are less likely to co-operate in producing basal shoots if the plants are trimmed. If varieties of this habit are severely pruned they may produce little if any suitable basal growth. If the worst should happen the plant will slip into a state of suspended animation or steady decline. Non-tufted varieties of viola are best propagated from healthy vigorous non-flowering lateral shoots, preferably those growing from close to the base of the plant or from healthy tip growth. Any shoots chosen as cuttings must be of solid texture. Mature stems ultimately become hollow and these hollow stems are unlikely to root readily or if they were to do so, to produce strong vigorous plants.

Non-tufted varieties of viola cannot be expected to offer a quantity of suitable propagation material to compare with that of the tufted varieties.

Seeds

Undoubtedly the most natural method of reproduction for the viola and violetta is by way of seed but it must be understood at the outset that there will always be the possibility of variation amongst seedlings and named hybrid varieties cannot be reliably reproduced from seed. When conditions are favourable and the plants are permitted to do so violas and violettas will form ripe viable seed with great profusion, but unless a particular named variety is grown in total isolation from other varieties of viola, violetta or pansy, and even then, any resulting seedlings will almost certainly exhibit considerable variation.

A measure of control can be exercised by not only growing the parent variety in isolation but by vigorously roguing out the seedlings which fail to inherit the characteristics of the parent. By retaining only for further breeding those seedlings which attain the required standard it should be possible to eventually harvest a strain of seed which will produce reasonably consistent results. There will however always be a degree of variation and the regular roguing out of inferior seedlings will be necessary in order to prevent a rapid deterioration of the strain.

Some varieties can and will produce seedlings which bear a remarkable resemblance to the parent but these varieties are in the minority and by far the majority of named hybrid violas and violettas should be expected to produce seedlings which can only be considered inferior in every respect to the parent.

New varieties

Amongst random seedlings there will inevitably be the possibility, however remote, of a plant showing exceptional characteristics which render it a suitable candidate for further trial and it is undoubtedly true to say that many of our finest named varieties have evolved in this manner.

In both theory and practice it is possible to influence the outcome by choosing which pollen we wish to apply to which stigma. There are many characteristics which combine to give our vision of an ideal viola or violetta - colour, fragrance, flower size, habit of growth, length of flowering season, disease resistance and many, many more. A plant may possess some desired characteristics but be sadly lacking in others and it is not unreasonable to suppose that if we cross breed this plant with another which possesses the characteristics which are lacking we may produce a seedling which has inherited the best characteristics of both. The situation can be influenced to some extent by ensuring that the flower chosen to bear the seed is emasculated by removing the pollen bearing stamens before they reach maturity, thereby preventing the possibility of self-pollination. The same flower must be totally isolated from any possible contact with pollen from elsewhere.

Ripe pollen from the flower chosen as pollen bearer must be brought into contact with the ripe stigma of the seed bearing plant and we have then done as much as we can to bring about a combination of the characteristics of the two plants. A reverse cross - the seed bearer becoming the pollen bearer and the pollen bearer the seed bearer - may well give rise to much the same result, but it is as well to be aware that whilst the ultimate result of all this may well prove disappointing there is always the possibility of experiencing the excitement of finding a seedling with the exceptional characteristics which will make it worthy of further trial and perhaps ultimate elevation to the status of named variety.

Viola or Violetta

The difference between pansies, violas and violettas is not always easy to distinguish. Basically violas are the result of a cross between the normal garden pansies and Viola lutea or V. cornuta. The resulting plants are more compact and tufted than pansies. Violettas are a smaller version of the violas, fragrant and without the whiskers that radiate from the centre of most violas.

A wide range of viola seed is available from Thompson & Morgan.