Irises, peonies and daylilies are extremely undemanding and resistant plants which require very little care. They might be the least difficult perennials of all. If you choose the right spot for them, they will reward you by flood of flowers every year. They are long-lived, e.g. the peonies will happily grow at one spot for many decades.
How to grow irises?
Choice of the spot
Bearded irises (whether the large-flowered tall or the dwarf ones) are rather xerophytic, which means they prefer very sunny spots which may be lightly shaded in the afternoon. They do not tolerate over-watered or very shaded locations. The Siberian irises grow well even in slightly humid, sunny or semi-shaded positions.
Soil
Bearded irises can do in all types of soil though most of all they enjoy well-drained, not too watered substrate. Irises form a rich root system which allows them to draw sufficiency of nutrients contained in the soil. They do not therefore require fertilizing, on the contrary, if over-fertilized they tend to suffer from root rot. The Siberian irises are also undemanding in terms of the soil – they can be planted to a more humid habitat then their cousins and prefer nutrient, not too drying brown earth.
Planting and maintenance of irises
Irises shall best be planted within two days after delivery. When planting the bearded irises in July, the rhizomes may be put into soil quite mildly with their top half exposed to the air. However, when planting them in late August or after, we recommend placing them ca. 3 cm under the soil surface to avoid the situation when frost pushes the rhizomes out of the soil in case they do not rooted well in autumn. After planting, irises shall be watered and if the weather is hot, watering shall be repeated towards evening at least once in 5 days. The Siberian irises will be grateful for more frequent watering (once in 2 days) after being planted. Planted irises may bloom as soon as in the following year though the richest blooming is to be expected in the 2nd and 3rd years after planting.
Irises require very low maintenance – after winter, dry leaves shall be removed and the soil around mildly loosened. If spring is very dry, we recommend watering them before blooming, at least occasionally. In warm, low-altitude areas, such as Prague surroundings or South Moravia, Acklandia servadei may appear. It is a small-sized insect whose maggots eat through flower buds and the irises then don't bloom. It only affects the tall bearded irises; the dwarf irises are not infested. That is why ca. 2 weeks before the tall bearded irises are about to bloom, they shall be treated by insecticide (e.g. Karate, Nurelle or Mospilan) and the spraying shall be repeated once again after a week. After full bloom, the faded stems shall be immediately removed by cutting them where the stem rises from the rhizome. If irises are planted for four or more years at one spot, they form rich clumps but bloom less and the flowers get smaller. That is why the clumps shall be divided. Dig the clump out and divided them to pieces. Select the largest rhizomes and cut their leaves to a 10-15 cm long fan. Shorten the roots (to ca. 10 cm) and plant them back to a loosened bed improved by compost. Keep the distance of at least 30 cm between the plants.
How to grow peonies?
Peonies are very undemanding to grow; especially their herbaceous species are one of the easiest ornamental garden plants. They are not predisposed to diseases and pests.
Choice of the spot
Majority of herbaceous and semi-woody species thrive in sunny habitats or places but moderately shaded in part of a day.
Soil
In the growing season, peonies demand nutrients and don't tolerate long-term watering of the substrate. Therefore they require nutritious, well-drained loamy soil with neutral or slightly alkaline pH. However, peonies are generally very adaptive and grow well in nearly any kind of soil.
Planting and maintenance of peonies
The most suitable period for peonies planting comes after the leaves fade, i.e. in October. Pot plants with sufficiently large root ball may be planted any time during the growing season.
Peonies may be planted in groups of high perennials in beds, as impressive solitaires, in groups around lawn edges or combined with ornamental shrubs.
The plants need sufficient space. To plant them, prepare a pit at least 40 cm wide and deep. If the subsoil is not drained well, provide a 10 cm drainage layer on the bottom (fine gravel, coarse sand), then a soil layer and only then plant the peony plant. When planting, the substrate may be enriched by universal, slowly-dissolving fertilizer (Osmocote) or by horn matter. The herbaceous species (especially the Lactiflora hybrids) shall only be planted with tops of their buds reaching 3 cm below the soil surface. The deeper planted plants flower either less or not at all. The semi-woody peonies shall be planted a bit deeper – with their buds 5 cm below the soil surface.
The newly planted peonies shall be richly watered. Peonies planted in autumn may only be watered once or twice after planting – depending on the weather. Plants planted in course of the season shall be watered regularly until they take roots and start to grow. Well rooted plants become very hardy – they shall only be watered in spring in dry weather lasts for long.
Care of the herbaceous peonies is very simple. Keep their surrounding free from weeds. After full bloom, cut the faded flowers. For winter, the herbaceous peonies die down which means that in early autumn their leaves start to fade and the nutrients are drawn down to the roots. The drying leaves shall not be cut in autumn; you can easily cut them in early spring before new leaves sprout from buds just below the soil surface. In the semi-woody peonies, the buds (from which the leaves sprout in spring) form on ca. 10-15 cm long woody stems, which is why faded stems shall be cut above these buds.
Peonies do not like replanting – their planting location shall therefore be permanent. Herbaceous peonies can live to 30 years, often even longer…
How to grow daylilies?
Just like peonies, daylilies are extremely undemanding for growing, hardy and not predisposed to diseases and pests.
Choice of the spot
Daylilies will most of all thrive on sunny locations but can also grow in semi-shaded places though they will not bloom as much as in full sun.
Soil
Daylilies prefer well-drained, sufficiently moist soils with a good amount of humus. They prefer a slightly acid soil reaction though slightly alkaline soils will suit them well, too.
Planting and maintenance of daylilies
The most suitable period of the year to plant daylilies is spring (March to May), possibly also autumn (September to October but at least 6 weeks before the first frosts). Pot plants may be planted all year round. If roots in the pot are densely crammed, divide them carefully before planting. When planting, spread the roots and cover them by soil so that the eyes are only 1-2 cm below the soil surface. Water thoroughly. The plants shall then be regularly watered until they take roots and start to grow. In the first year after planting, daylilies usually bloom sporadically. In the following years, the number of leaves and flowers increases; the plants grow more robust and reach their top between the 4th and 6th years. Later the stems and flowers become smaller and the clumps shall be divided, best in spring. When doing so, cut the roots by one quarter to one half and the leaves to ca. 20 cm. This way you support fast rooting and subsequent growth.
And how to treat daylilies in course of the year?
In spring when heavy frosts are no longer to be expected, cut dry leaves from the previous year. In April, you can add Cererit to support growth and blooming. Water in spring – especially in dry years. In August, remove the faded stems. Before the frosts arrive, cover the more sensitive evergreen varieties by spruce branches, dry leaves or non-woven fabric.