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ProEnvironment

ProEnvironment10 (2017) 238 - 244

Original Article

Herbaceous Companion for Iris in Cluj County

CRIȘAN Ioana1, Roxana VIDICAN1, Orsolya BORSAI2, Andrei STOIE1, Vlad STOIAN1

1Faculty of Agriculture. University of Agricultural Science and Veterinary Medicine Cluj – Napoca, Calea Manastur St., No. 3 – 5, 400327 Cluj-Napoca, Romania 2Faculty of Horticulture. University of Agricultural Science and Veterinary Medicine Cluj – Napoca, Calea Manastur St., No. 3 – 5, 400327 Cluj-Napoca, Romania

Received 29 November 2017; received and revised form 6 December 2017; accepted 19 December 2017 Available online 30 December 2017

Abstract

Irises are beloved spring garden plants that do not require much care. Apart from their decorative value in landscape they also bring environmental benefits because they contribute to the improvement of soil stability while some such as Iris pseudacorus was proven to have phytoremediation capacity. In order to achieve the highest possible result for the customer or public by using these species in green spaces, the following aspects must be taken into consideration: hardiness, location, landscape color scheme and plant associations. The aims of this study were to identify the potential use of Iris plants in green urban areas from Cluj County, and to establish suitable plant associations with other low-maintenance herbaceous flowering plants for easy landscaping.

Keywords: hardiness, phenology, iris, green space, spring , temperate garden.

1. Introduction He concluded that although old irises are not The use of Iris sp. as garden plants dates back rare in European gardens they remain nameless [2]. to the time of Thutmose III (1469 B.C.) from ancient Nowdays, the color of iris plants is the most Egypt when irises were brought from Syria to be important value of garden artistry [10]. The wide cultivated in the pharaoh gardens [15]. Irises were variety of species and available today makes well known also in ancient and found in sure there exists a suitable iris for every type of gardens during the medieval times. As evidence garden [11]. For a successful integration of Iris plants come their representations in art and various written in landscape design one must keep in mind the accounts related to their use [6]. Their integration in importance of planting location, plant needs, the landscape is mentioned as early as the beginning of color scheme and as well as the presence of XIXth century when several Iris species together with companion plants [1]. Irises play an important role in their flowering time were described as suitable for any type of garden from classic to aquatic, water-wise perennial border [8]. Regarding old garden irises, gardens and rockery [5]. Blažek reports that in Romanian villages, he found The most cultivated irises in gardens tetraploids of Iris aphylla as well as irises related to worldwide are the tall bearded hybrids with Iris ‘Amas’, similar with the bitone or bicolor clones of germanica cultivars being the most easily Iris trojana or Iris germanica. recognized, followed by the shorter bearded types especially Iris pumila cultivars, and last but not the * Corresponding author. least by Siberians represented the best by Iris sibirica Tel: +40-264-596384 Fax: +40-264-593792 as well as the Japanese with the well-known Iris e-mail: [email protected] ensata cultivars that have some of the largest flowers [1, 3 10, 21].

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The presence of irises in landscape design Garden of Komarov’s Botanical Institute, Russia [21] brings several environmental benefits. Iris Meiji Jingu Inner Gardens and Suigo Sawara pseudacorus for example, was studied for its Botanical Garden from Japan [17, 18] as well as phytoremediation capacity of aquatic environments Presby Memorial Iris Gardens from United States [9] and was demonstrated to have a good efficiency [23]. Historic Iris Preservation Society provides a list in treating polluted urban wastewater [14] while the of gardens found around the world where old garden leaves were proven bioindicators for contamination cultivars can be admired [19]. of bottom sediments by heavy metals [12]. Iris plants can be found in public green spaces Also, irises are considered able to improve soil and botanic or private gardens throughout stability [16]. Currently there are some well-known Transylvania and are used either as single plants or gardens housing Iris collections around the world: associated with other cultivars or other plant species Giordino dell’Iris from Italy [20], Monet Gardens (Fig. 1). Iris species that can resist temperatures of - from France [22], Iridarium from the Botanical 20°C are suitable for Cluj County, Romania [4].

a) Iris as roadside plants in a residential district

b) Iris plants near a pond c) Iris with Aquilegia sp.

d) Iris in mixed mass planting e) Iris in isolated groups

Figure 1. Examples for the use of Iris plants in Transylvania: a) in Gheorgheni district of Cluj-Napoca; b), e) in Jibou Botanical Garden; c), d) at UASVM Cluj-Napoca [24]

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This study was carried out in order to throughout private gardens as well as in the local investigate the potential use of Iris plants in Cluj cemeteries. The most common taxa met belong to the County green areas and to identify a selection of tall bearded group, with Iris germanica cultivars accompanying spring herbaceous flowers for the being the most widespread. most common Iris species cultivated in Cluj County As it can be observed from the utilization chart area. (Fig. 2), in nearly half of the times irises are found as single plants or in isolated groups not associated with 2. Material and Method other flowering species with similar flowering time. In this case irises are used for blooming succession, For this study, firstly were conducted filling the gap between the early spring flowering observations regarding locations where irises can be species and the summer flowering ones. met in Cluj-Napoca urban area and their current state In other cases, irises are found associated with of use and secondly were conducted phenological several herbaceous flowers such as columbine, late observations focused on the flowering time of the tulips, poppy and herbaceous . Sometimes wild and cultivated plants during spring of 2017 in other non-herbaceous plants, like roses are found Cluj County and neighboring areas. planted nearby iris plants. One can notice that current accompanying 3. Results and Discussions assortment used is not very wide, and there are many other suitable species that at the same time In urban area of Cluj-Napoca irises can be seen which could be used in association with various in green spaces surrounding the apartment blocks and hardy iris species, as it will be shown further.

Figure 2. The utilization of May-flowering Iris in Cluj-Napoca

Because texture in the garden is created advantages of using wild species in association with through contrast, this can be achieved by pairing the Iris plants are that these autochthonous species are iris plants with a variety of other plants (Table 1, Fig. more resilient and need less maintenance. Besides, it 3). The potential herbaceous companion plants of Iris is important to choose species as a companion plants can be divided in two categories: from the wild flora, that harmoniously match the color scheme of the and cultivated plants. The most remarkable garden. Associated plants also need to have similar

240 CRIŞAN Ioana et al./ProEnvironment 10(2017) 238 - 244 environmental requirements like moisture, light and flowers of Corydalis solida and Primula vulgaris. shade. Although most Iris species prefer full sun, at The flowering period of Iris reticulata is overlapping the beginning of spring they can be combined with with several other spring flowers with a longer plants that usually grow either in open meadows flowering time as shown in Table 1. Iris reticulata (Primula sp., Bellis perennis) or near trees (Hepatica reaches a maximum height of 15 cm like other wild transsilvanica, Anemone nemorosa) because at their species such as Tussilago farfara with bright yellow bloom time, the leaves of the trees are just about to flowers widespread in Cluj County, which can be a appear. For late flowering spring plants, the very good companion plant for this Iris, contrasting requirements regarding their environmental needs well with the deep blue and violet-purple color of the can be very different; usually these species either flowers. There are also other wild species with tolerate shade or prefer higher substrate moisture or yellow or white flowers that would contrast well with not. Table 1 includes the possible wild and cultivated the flowers of this bulbous iris. It can be observed in herbaceous flowering species that could be properly Table 1 that species recommended do not risk associated with Iris species due to their overlapping overshadowing this tiny plant, all having a similar flowering time. height. However, Scilla sp. has blue flowers that Iris reticulata flowers in the second half of might not pair well with this iris alone, thus, a few March. In this period of early spring, in Cluj County other species should also be included to improve the the green areas are spotted with the emblematic combination quality with bright colored flowers.

Table 1. Peak flowering time of hardy Iris species and their potential companion plants in Cluj County Species Flowering time Herbaceous companion flowers

Iris reticulata 16-31 March Corydalis solida, Hepatica transsilvanica, Anemone nemorosa, Tussilago farfara, Primula vulgaris, Scilla bifolia, Scilla sibirica, Leucojum aestivum Iris pumila 01-15 April Leucojum aestivum, Lamium purpureum, Adonis vernalis, Viola odorata, Bellis perennis, Narcissus pseudonarcissus, Ranunculus ficaria, Pulsatilla montana, Fritillaria meleagris Iris aphylla 16-30 April Primula veris, Taraxacum officinale, Bellis perennis, Tulipa gesneriana, Narcissus poeticus, Muscari sp., Phlox subulata, Alyssum saxatile, Fritillaria imperialis Iris pseudacorus 01-15 May Veronica chamaedrys, Myosotis arvensis, Allium sp., Phlox Iris germanica subulata, Alyssum saxatile, Aquilegia vulgaris, Paeonia lactiflora Iris pseudacorus 16-31 May Paeonia lactiflora, Thymus vulgaris, Arnica alpina, Scutellaria sp., Iris germanica Dracocephalum ruyschiana, Phlomis tuberosa, Papaver orientale, Iris sibirica Cerastium tomentosum, Salvia officinalis, Lupinus polyphyllus, Linum sp., Veronica austriaca, Penstemon hirsutus, Hemerocallis middendorffii, Scabiosa sp.

Wild Iris pumila has yellow or purple the dark shade of this Iris species. Due to their similar flowers, yet there are cultivars of various colors height, they could be used to create a focal point in today. The species Viola odorata, Pulsatilla montana any garden or public green area. Phlox subulata can and the Fritillaria meleagris could be used as be a different companion plant, covering the ground companion plants for the yellow flowered plants, near and between the other associated plants. In while the species Adonis vernalis, Ranunculus larger combinations Fritillaria imperialis, due to its ficaria, Leucojum aestivum, Bellis perennis, height can be used in the background. Narcissus pseudonarcissus are suitable for purple- During May, the tall irises are about to flowered Iris pumila. The height of this Iris is of flower. The associated plants proposed (Table 1) about 25 cm and some of the plants recommended as have different habitus and height, making their companion flowers have a shorter height, thus there matching more difficult. Beresford-Kroeger (2004) is no possibility for them overshadowing the iris, stated that tall bearded irises are difficult to integrate even if planted close to each other. in a garden design in large numbers due to their very Iris aphylla reaches a maximum height of strong vertical planes, and their neighboring plants 15-30 cm and has deep purple flowers that suits well should have tiny or dissected foliage to obtain a with the short and bright Taraxacum officinale and harmonious combination [1]. Bellis perennis that can be planted in groups around Iris germanica plants pair very well with this iris. Narcissus poeticus, Alyssum saxatile and ornamental Allium sp., however the composition Primula veris make the most excellent contrast with could be completed with shorter plants to break the

241 CRIŞAN Ioana et al./ProEnvironment 10(2017) 238 - 244 monotonous vertical lines. Aquilegia sp. is a very white to light yellow and light blue. Papaver good accompanying plant. Also, the small plants with orientale, Lupinus polyphyllus and Salvia officinalis tiny flowers like Veronica sp., Myosotis arvensis, also suit well the light-colored Iris cultivars. There Phlox subulata and Alyssum saxatile could be used are a series of short plants both wild and cultivated for this purpose during the first and also the second that could also complete the iris compositions during part of May. Herbaceous peony (Paeonia lactiflora) the last half of May. Plants with light pink flowers has leaves that are a good match for the vertical like Thymus vulgaris and white-flowered Cerastium sword-like Iris germanica leaves as well as for the tomentosum can be spread at the base of the tall grass like leaves of Iris sibirica. The soft powdery bearded irises to sustain the chromatic heaviness of pink of the classic peony flower as well as the intense the dark flowered Iris cultivars. Phlomis tuberosa colored ones should never compete with Iris flowers could be planted in groups near iris plants. of the same colors. Therefore, the Iris cultivars Dracocephalum, Scutellaria and Scabiosa sp. can be chosen should have other chromatic tones, from spread in smaller groups.

Hepatica transsilvanica Anemone nemorosa Primula vulgaris

Ranunculus ficaria Pulsatilla montana Leucojum aestivum

Fritillaria meleagris Alyssum saxatile Phlox subulata

Papaver sp. Veronica austriaca Allium sp.

Figure 3. Easy landscaping companion plants for Iris in Cluj County from mid-March to end of May [24]

Regarding the integration of spring flowers in landscaping in temperate climate are in agreement landscape design, the literature is very vast, and the with the observed phenological stages for the main recommendations cannot always be extended to other companion species [1, 7, 10]. In the scientific geographical regions. However, most of the reviewed literature, the following species are recommended to sources that refer to the integration of Iris plants in join the irises from early to mid and late spring:

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Veronica sp., Salvia sp., Pulsatilla sp., are recommended for surrounding irises in open border 4. Conclusions while at the margins of shady areas Tiarella sp. could be used. In landscape planning and design using Iris The species Primula sieboldii and Lysimachia plants, texture and balance of the composition can be punctata with bright flowers can join irises in the achieved by using neighboring and background composition. Also as companion plants for garden plants that create contrast and at the same time are in irises are mentioned edge plants that thrive at the chromatic equilibrium with hues and patterns of iris margins of sun and shade, like Phlox divaricata, flowers. The earliest iris to flower in Cluj is the Lamium maculatum, Ranunculus repens, bulbous Iris reticulata, followed by bearded and Polygonatum humile, Primula sp., and Viola sp. beardless rhizomatous species: Iris pumila, Iris The taller iris species are indicated as suitable aphylla, Iris pseudacorus, Iris germanica, Iris to be paired with bulbous species like Fritillaria sibirica. Each of them can be accompanied by a imperialis and Allium karataviense, but also with mid series of spring herbaceous species with same or late spring flowering species like Papaver flowering time. The most common flower species at orientale, Delphinium sp., Lupinus sp. [1, 10]. the start of spring in Cluj County are Corydalis When it comes to the planting location, some solida, Hepatica transsilvanica and Primula authors recommend bearded irises to be planted vulgaris. For the first part of April Viola odorata and toward the front of the border in a position to increase Bellis perennis can be seen almost everywhere in the perceived depth. green areas while in the second half of April Tulipa The tall bearded irises can be used as part of a sp, Taraxacum sp. and Muscari sp. are the most foundation planting. Siberian irises are indicated as common flowers in Cluj green spaces. In May, the suitable for rain gardens, riparian buffers, around ornamental Allium sp., Aquilegia vulgaris, Paeonia ponds and water features. lactiflora and Papaver orientale are in bloom in For small gardens flower reflection of the private gardens. irises planted on the edge of water can be used to The results of this study show that Iris species create the feeling of space [1, 13]. There are also cultivated in Cluj County can be paired with a lot of other Iris species less well-known in Romania that different herbaceous flowering species either wild or could be tested in local climate such as Iris fulva that cultivated to achieve an excellent visual texture and a belongs to Louisiana iris group, because it is as hardy hardy, low maintenance garden or green space in the as Iris germanica [1]. local climate.

References

[1] Beresford-Kroeger D., 2004, A Garden for Life: The [7] Holland-Spicker S., 2014, "Talking Irises" tall bearded Natural Approach to Designing, Planting, and Maintaining irises in your landscape - Using a variety of plants is a North Temperate Garden, University of Michigan Press, beneficial in your iris beds, World of Irises - The Blog of 86-100. The American Iris Society, https://theamericanirissociety. blogspot.com. [2] Blažek M., 2016, ‘Amas’ and ‘Macrantha’ Known and Unknown Irises, Roots Journal of the Historic Iris [8] Loudon J.C., 1824, An Encyclopaedia of Gardening: Preservation Society 29(1), 10-14. comprising the theory and practice of horticulture, floriculture, arboriculture and landscape-gardening, [3] Brown D., 2015, Iris for northern gardens, University Paternoster-row, 867-871. of Minnesota Extension, Department of Horticulture, http://www.extension.umn.edu. [9] Marcacci S., J.P. Schwitzguebel, 2007, In: Methods in Biotechnology, vol 23: Phytoremediation Methods and [4] Crişan I., A. Stoie, M. Cantor, 2016, Overwintering of Reviews by Neil Willey (ed.), Chapter 19: Using some hardy Iris species in Agrobotanical Garden UASVM Phylogeny to Predict Detoxification of Triazine Cluj-Napoca, Agriculture Science and Practice Journal Herbicides, Humana Press Totowa, New Jersey, 234. 99(3-4), 6-14. [10] Norris K., 2012, A guide to bearded Irises, Timber [5] Fleming-Hayes R., D.C. Zlesak, 2015, Iris, Yard and Press, 24-59. Garden, University of Minnesota Extension, http://www.extension.umn.edu/garden/yard- [11] Russ K., B. Polomski, 1999, Iris, Clemson garden/flowers/iris. Cooperative Extension, HGIC 1167, 1.

[6] Helvey J., 2009, Irises: Vincent van Gogh in the [12] Parzych A., M. Cymer, K. Macheta, 2017, Leaves and Garden, Getty Publications, Los Angeles, 25. roots of Typha latifolia L. and Iris pseudacorus L. as

243 CRIŞAN Ioana et al./ProEnvironment 10(2017) 238 - 244 bioindicators of contamination of bottom sediments by heavy metals, Limnological Review, 16(2), 77-83. [18] ***, 2015, 10 Best Iris Gardens to Visit in Japan, https://www.kyuhoshi.com. [13] White S., A. Dabbs, 2016, Rain garden plants: Iris sibirica, An Informational series from Clemson [19] ***, 2016, Guardian Gardens Iris List, Historic Iris University’s Water Resources Program Team, 325, Preservation Society http://www.historiciris.org. http://www.clemson.edu/public/carolinaclear. [20] ***, 2017, Il Giardino dell’Iris, Societa Italiana [14] Zhang X.B., P. Liu, Y.S. Yang, W.R. Chen, 2017, dell’Iris, http://societaitalianairis.com. Phytoremediation of urban wastewater by model wetlands with ornamental hydrophytes, J Environ Sci (China), [21] ***, 2017, Iridarium, St. Petersburg Komarov 19(8), 902-909. Botanical Institute, http://flower-iris.ru/en.

[15] ***, 2014, Iris: A Brief History, Dep. of Plant [22] ***, 2017, Giverny Flowers: Irises, The Claude Sciences, Univ. of Missouri, https://ipm.missouri.edu. Monet Foundation, http://fondation-monet.com.

[16] ***, 2014, Lakeside-Design, City of Austin [23] ***, 2017, Presby Memorial Iris Gardens of Watershed Protection, https://www.austintexas.gov. Montclair, http://presbyirisgardens.org.

[17] ***, 2014, Top 5 Iris Gardens in the Tokyo Area, [24] ***, Original photos by Ioana Crișan. https://uncoveringjapan.com.

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