Sunray Yellow

Description

An annual ornamental herbaceous plant, also known as the sunflower, extremely versatile, capable of enhancing green spaces such as flowerbeds or borders, as well as terraces and balconies in planters or pots, with its characteristic inflorescences bearing petals in warm, vibrant colours clustered around the typical disc-shaped receptacle, often chocolate-coloured, which appear from spring until late summer or early autumn, depending on the variety, and are also attractive to beneficial insects such as bees and butterflies; furthermore, some birds are particularly fond of its fruit, known as achenes, which are rich in oil.

Easy to grow, it tolerates even hot summer climates if watered regularly; it is also suitable both as a single specimen in pots and for creating compact, uniform, monochromatic clumps, as well as for mixed compositions with other ornamental plants or in intercropping/combination with vegetable species such as cucumbers, peppers and tomatoes.

Species video

https://youtu.be/Fd5nOrC-qHQ

Variety description

An extremely eye-catching seasonal plant with large yellow flowers. As well as the central flower, it can produce other side flowers and continue to flower for quite some time. A compact plant that is also suitable as a houseplant. The seeds, which are edible, can be harvested.

Division

Angiospermae

Class

Dicotyledons

Family

Asteraceae or Compositae

Order

Asterales

Genus

Helianthus

Species

annuus

Origin and distribution

Belonging, like Jerusalem artichoke, to the genus Helianthus, it is a species native to the northern United States, Canada and northern Mexico where it was a primary source of food for the local populations. It arrived in Europe at the end of the 1500s where it was immediately appreciated as a plant for both ornamental and productive use. From the 1800s to the present day, a series of hybridisations have taken place, leading to many cultivars of different heights, expanding the colour range of the flowers and ensuring greater plant compactness.

Curiosities and special features

The nameHelianthus derives from the Greek helios and anthos, meaning ‘flower of the sun’, referring to heliotropism – that is, the plant’s tendency to orient its inflorescence towards the sun; the specific epithet, annuus, emphasises the duration of the plant’s growing cycle.

Local people in the species’ areas of origin used to grind the seeds to make flour for baking bread and cakes, or to extract a greyish-purple dye; they also used an infusion made from the flowers for medicinal purposes.

Inflorescences can be used in cut-flower compositions, provided they are placed in fresh water immediately.

Lifespan

Annual Plant.

Where to plant

Mainly used to add colour and vibrancy to balconies, window boxes and outdoor planters

Plant height

The plant height ranges from 0.2 to 0.35 m, a feature visually emphasised by the striking inflorescences that rise erect amongst the foliage.

Inflorescence

Inflorescence

Flower size

A medium-sized flower , which is large when compared with those of other varieties belonging to the same species.

Flowering period

The spectacular inflorescences add a splash of colour and light from mid-spring to late summer, lasting between 120 and 150 days.

Leaf

The leaf has a heart-shaped lamina, silky to the touch.

Leaf colour

Solid colours.

Fruit

‘Semi’ has the value ‘Semi’ as its part of speech.

*Note: the system rule stipulates that the first word must be ‘Semi’, so I was unable to use ‘Il/La Semi...’.*

Stem

The stem isherbaceous, cylindrical and sturdy; the plant has no thorns.

Flower

The flower is daisy-shaped and ranges in size from medium to large. The petals are solid in colour. It flowers from mid-spring to late summer, with a flowering period of between 120 and 150 days. It attracts bees.

Growth

It shows medium to vigorous growth.

Habit

It displays its characteristic erect plant habit, which gives it a prominent role within mixed compositions, thus becoming an eye-catching focal point.

Branching

It naturally has little branching.

Use

Known to everyone as the sunflower, thanks to its warm, vibrant flowers that are synonymous with summer, it is widely used in:

Outdoor ornamental use Indoor ornamental use

Ideal climate and temperature

The ideal temperature is between 10 and 25 °C; however, it is a plant that shows good climatic adaptability and can also tolerate hot climates. The biological temperature range is between 5 and 35 °C.

Soil

The ideal soil for proper sunflower development is medium-textured, peaty, fertile and well-draining; for use in pots and planters, a substrate for spring plants based on fibrous peat and perlite is recommended.

Sun exposure

It preferssun exposure infull sun or a light source indoors; to ensure the best flowering, place it in the brightest spot possible whilst ensuring it receives adequate water, particularly on the hottest, driest summer days.

Difficulty

It iseasy to grow, and the level of management required to ensure proper vegetative growth is, on the whole, low.

Hardiness

A variety characterised by itshigh hardiness, which gives it added value; it is particularly appreciated by gardeners and gardening enthusiasts of all levels of experience.

Growing tips

We recommend the following measures and cultivation practices aimed at achieving the best possible growth vigour:

Expose the plant to as much light as possible Keep the medium consistently moist

Soil preparation

Before spring planting, carry out shallow digging, removing any weeds, large stones and residues from previous crops. Then work in organic or slow-release chemical fertiliser, which will provide the nutrients needed for the initial growth phase following planting. Furthermore, if the soil/medium is compact and poorly drained, we recommend adding some sand. Continue by chopping up the denser, coarser clods with a hoe; finally, carefully level the surface and prepare the planting holes at a suitable density.

pH

It prefers a soil or substrate pH ranging from sub-acidic to neutral, between 6.0 and 7.5.

Combinations with other plants

The sunflower is the ideal choice not only for creating bright, compact and monochrome groups, but also for mixed compositions in harmonious combinations with other ornamental species such as Anthemis tinctoria, Celosia, Cineraria maritima, Coleus, Coreopsis, Gaura and Zinnia elegans.

Planting

As with any ornamental bedding species, planting must be carried out at a suitable density to ensure the plant reaches its full growth vigour, thereby achieving a balanced and visually harmonious final effect; an average planting density of 8 plants per square metre is therefore recommended. When transplanting, ensure that the root ball is moist, position the seedling so that it is buried up to the first set of cotyledon leaves, and water immediately afterwards.

Watering

A plant with medium to high water requirements. It is suggested to use rainwater or, alternatively, tap water, either by hand-watering or via an irrigation system. During repotting, avoid allowing the plant to dry out, as this can cause stress to the young plant and compromise its subsequent growth. Thereafter, always keep the soil/medium moist, avoiding both waterlogging – which can cause fungal diseases and subsequent root rot leading to the plant’s death – and periods of drought, which can result in the leaves turning yellow. If sowing seeds, it is advisable, after completely covering the seed with soil, to keep the compost moist until the seedling emerges.

Fertilising

Before transplanting, carry out a background fertilisation by burying organic or slow-release chemical fertiliser. During the spring-summer period, following proper post-transplant settling, apply a balanced liquid fertiliser specific for ornamental plants to the substrate or soil, to be diluted in the irrigation water according to the appropriate doses and frequencies as indicated on the relevant information label.

Propagation

Reproduction/Propagation is by sowing.

Edibility for humans

In some varieties, the achenes – that is, the fruits often referred to as seeds – are edible when dried. Ornamental varieties are not edible.

Toxicity for humans

No known toxicity following ingestion. Take the variety into account.

Pet safety

There are no known cases of toxicity in pets following ingestion; consider the specific circumstances and consult your vet before administering the product.

Tip

Avoid drying out the plants so that the basal leaves do not turn yellow and always fertilise abundantly.