How to Grow Stock Flower

One of the most popular cottage garden plants, the stock flower is prized for its colorful blooms and clove-like scent. Heritage varieties are particularly fragrant.

Said to have been introduced to the United States by Thomas Jefferson in the late 18th century, these distinctive flowers were a popular plant during the Victorian-era. In England these colorful plants are also known as Gilly Flowers where they are seen as a sign of deep affection.

Popular for their colorful long lasting flowers, that are equally at home in fresh floral bouquets or dried arrangements as they are in the garden, stock flowers can also be used to garnish salads and deserts.

If you want to learn more about growing the stock flower, this guide is for you.

Matthiola plants are both colorful and fragrant.

What is a Stock Flower?

The stock flower (Matthiola incana) is part of the brassica family. The blue-green leaves of the plant can resemble those of a cabbage. This means that when the blooms fall from Matthiola incana plants they can look like a brassica plant gone to seed. Also known as Hoary, Brompton or Vintage Stock, these plants are typically hardy in USDA Zones 7 to 10.

The stock flower is one of the most fragrant plants you can add to your garden. Filling spaces with its sweet, spicy aroma make the most of these fragrant plants by positioning them at nose height. This makes it easier to appreciate the aroma.

Blossoming in a range of colors from white and pink or rose to deep jewel tones and rich reds, blues and purples, there are Matthiola plants to suit every planting scheme.

Taller varieties can reach up to 3 ft, most achieve a mature height of between 12 and 24 inches. Dwarf types, typically growing to a height of 8 to 12 inches, are also available. These compact specimens are great for planting in smaller or container gardens.

Depending on the type, stock flower blooms can be either clustered tightly together or spaced loosely across the spiky stems. Double blooming types are just as common as single flowering cultivars.

A cool weather specimen, Matthiola plants bloom from early spring to summer. Once the temperature exceeds 60 ℉ the plants cease to bloom.

Matthiola blooms in a range of colors. Matthiola by yewchan / CC 2.0

Often classed as a biennial plant because it blooms and sets seed in the second year, Matthiola plants can be grown as an annual, biennial or perennial depending on the climate.

In cooler climates, the stock flower is best grown as an annual. The plants are unlikely to survive the first few frosts. In warmer areas the Matthiola plant is perennial and hardy. In favorable conditions it is capable of surviving for several years, producing sturdier woody stems each year until the heat of summer finally takes its toll.

Different Matthiola Varieties

There are at least 60 different types of Matthiola plant.

While many cultivars have a compact, upright growth habit, spray types of stock flower typically have multi-stemmed loose terminal blooms. Upright or columnar types produce a single stem on which sits the dense floral cluster.

Like the snapdragon, Matthiola blossoms form sequentially from the bottom to the top of the stem. The floral stems sit above lush, slightly hairy green or gray-green leaves. The floral petals are arranged in either single or double rows, depending on the cultivar and emit a spicy sweet fragrance.

One of the most unusual is Matthiola bicornis or Evening Scented Stock. Typically producing larger blooms, like Matthiola longipetala or Night Scented Stock, this plant opens after the sun sets, filling the evening air with a powerful fragrance.

Night Scented Stock is largely grown for its fragrance, the blooms are not as visually attractive as other cultivars. These plants also rarely set seed because the flowers open at night, when pollinators are absent.

Planting Evening or Night Scented and day flowering types together fills outdoor spaces with a pleasing fragrance throughout the day and night.

Other popular types of Matthiola plant include:

• Cinderella is a compact, dwarf type rarely exceeding 11 inches. Despite its small stature, Cinderella produces eye-catching double blooms in pastel shades. Cinderella is a unique type of Matthiola plant because even though it is small it produces double blooms that are deeply fragrant,
• Legacy is a double blooming type, reaching up to 2 ft tall. Legacy blooms emerge in bright vivid shades such as purple and crimson. Legacy is a fragrant hybrid cultivar which is ideal for modern gardens,
• Starlight Sensation produces dramatic single blooms in a range of colors. Typically reaching 18 inches in height, like many colorful cultivars, if you are growing from seed you can never be entirely sure which color you will get. Starlight Sensation reliably blooms throughout the spring and early summer months,
• Ruby Punch produces richly fragrant ruby red blooms,
• Iron is a series of large double blooming plants. Popular for floral arrangements, the blooms of Iron sit on sturdy stems,
• Antique Pink is a two-tone pink usually double bloom with contrasting, green centers.
• White Goddess is an elegant cultivar which produces large, sweetly fragrant double blooms. A hybrid Matthiola cultivar, White Goddess blooms often have a yellow-green center,
• Virginia Spring Sparkle is an old fashioned variety that produces blooms in pastel hues with dark centered eyes. It is ideal for spring and fall floral displays.

The distinctive night scented stock flower. Night Scented Stock by Dean Morley / CC 2.0

How to Grow a Stock Flower

You can either purchase Matthiola seedlings from a garden center or plant nursery or grow the plants from seed.

In USDA Zones 7 to 10, you can sow seeds outside in pots or directly into the garden in the fall for early spring blooms the following year.

In cool regions, you can start the seeds 8 to 10 weeks before the last predicted frost date. Start the seeds in small pots of individual seed starter cells filled with fresh potting soil.

MIXC Seedling Tray Starter Trays come with a lid which has an inbuilt humidity vent. This enables you to control the temperature and humidity levels around the seedlings.

Moistening the soil helps the seed to stay in place. Sow the seeds as thinly as possible before covering with a thin layer of fresh potting soil and placing in a light position.

Matthiola seeds require a temperatures of 65 to 75 ℉ to germinate. Germination usually takes 10 to 14 days. This can be slightly longer in cooler conditions.

Water the soil regularly, until the seeds germinate. This is best done with a Plant Mister Spray Bottle. Using a hose or watering can runs the risk of drowning the seedlings.

https://www.youtube.com/watch?v=VJZ_wsVsPPc

Following germination, continue to care for the seedlings undercover until the last frost date has passed.

As the developing seedlings grow, water the soil twice a week. Aim to keep the soil moist. Do not overly soak or drench the soil.

Harden off the seedlings and plant to the same depth, around 2 inches deep, as in the pot or starter trays. When planted the crown of the plant should sit just below soil level.

Different varieties have different spacing requirements. In general aim to space the plants 6 to 7 inches apart. Larger specimens may require spacing up to 20 inches apart.

As seedlings mature, pinch back the budding growing tips. This encourages more dense floral clusters.

You can also grow stock flower plants in pots and planters. Fill your chosen container with fresh, well draining potting soil and plant as described above.

For floral buds to set, your Matthiola plants must be exposed to temperatures under 60 ℉.

Cold Weather Exposure

Chilling is the most complicated part of growing a stock flower. The plants require exposure to a period of cold weather before they can set bloom. Early flowering types require exposure of around 2 weeks to temperatures of 50 to 55 ℉. Later flowering varieties can require up to 3 weeks of exposure to cooler temperatures.

While the stock flower requires exposure to cooler temperatures to set floral buds, do not expose the plants to temperatures below 50 ℉ for a prolonged period of time. This can damage the roots.

If the plants do not experience a chill period, flowering may be sparse or non-existent.

If you are growing in an area that does not experience exposure to colder periods you can purchase stock seedlings that have already had cold treatment from specialist plant nurseries.

In cooler areas, the easiest way to ensure that the stock seeds get a blast of cold weather is to start them undercover, in a greenhouse or cold frame at the right time of year. This is usually late winter or early spring. Check the back of the seed packet for precise sowing times, this can vary depending on the variety you are growing and your local climate.

Where to Grow

The Matthiola plant is best placed in a rich, neutral soil.

Plant in an open, sunny position. Stock flower by Paul Sullivan / CC 2.0

Best planted in cooler temperatures, the stock flower may survive the first frosts of fall but will die when exposed to colder temperatures for a prolonged period. The plants also struggle if humidity levels are too extreme. Ideally the plants should be exposed to tropical conditions and consistently moist soil.

Most Matthiola cultivars are hardy in USDA Zones 7 to 10. Depending on the climate, you can cultivate these plants as either biennials or short-lived perennials. If cultivated as a perennial, like another flowering perennial the Snapdragon, the stem grows sturdier and woodier each year.

If your garden does not experience a winter freeze the stock flower can be cultivated as a biennial.

If you are cultivating the stock flower as an annual plant, either from seeds or seedlings, it is a great plug plant filling awkward spots in spring and summer floral beds.

Attractive on their own you can also plant the stock flower in a cottage garden or floral planting scheme. Planting amongst other plants that share similar maintenance needs helps to make ongoing care easier. Other floral plants with similar care needs include:

• Larkspur,
• Dianthus,
• Snapdragons,
• Petunias.

Best placed in full sunlight, the stock flower tolerates partial shade in favorable climates.

Plants growing in partial shade require 2 to 3 hours of sun a day in addition to lots of indirect sunlight. This encourages flowering.

Avoid planting in areas that enjoy too much hot or bright light. This overwhelms the plants. In open sunny gardens a plant shade such as a Cool Air Shade Cloth can be used to protect the stock flower from too much intense afternoon sun. The plants should be protected from the intense afternoon sun. Instead plant where they can bask in the bright morning sunlight.

The soil should be loose and well draining. It should also be neutral or as close to neutral as possible. If your soil is too acidic, working in wood ash or lime helps to neutralize it. A soil test kit tells you the pH level of your soil.

Caring for Matthiola Plants

Once planted and established, these are pleasingly low maintenance plants.

Regularly weed around the base of the plants. Weeds can quickly grow and smother smaller specimens, depriving them of the necessary light and nutrients that they need to thrive. Our guide to the best weeding tools will help you to keep your garden beds neat and tidy.

If you don’t want to regularly weed around your stock flower plants, place a layer of organic mulch around the plants. This suppresses weed growth. A layer of mulch also helps the soil to retain moisture and prevents heat sensitive plants from becoming overly hot.

As with other plants, it is important to keep the soil neat and weed free. Source: Brompton Stock by Louise Joly  / CC 2.0

Popular for their upright growth habit if you are planting Matthiola plants in exposed positions you may need to support taller types by loosely tying then stems to a Minifa Bamboo Stake.

When to Water

Once established you need only water your stock flower plants during periods of dry weather or drought. In most cases average rainfall is enough to keep the soil moist and the plants happy. During hot or dry spells the plants require more regular watering.

Be careful not to overwater the growing plants. Water only when the top layer of soil feels dry to the touch. Too much water can cause the leaves to yellow. If not amended, overwatering can lead to more serious issues such as root rot developing.

When watering your plants, aim to water only the soil around them, keeping the leaves as dry as possible. This helps to keep humidity levels low. These plants struggle in highly humid conditions. Keeping the foliage dry during watering also helps to prevent issues such as powdery mildew from developing.

Do I Need to Fertilize My Plants?

Whilst not the heaviest feeding plant, an occasional dose of fertilizer helps to promote both healthy growth and blooming.

Apply a general purpose fertilizer for flowering plants straight after planting. How much you need to apply depends on how many plants you have planted and the product you are using. Consult the information on the fertilizer packet for exact dosage amounts. Repeat this dose one month after planting.

A regular dose of fertilizer promotes growth and flowering.

How to Prune

Regular pruning helps to keep your stock flower plants looking neat. It also encourages new growth and, on some cultivars, more blooms to form.

Prune away or deadhead spent blooms. As well as encouraging more blooms to form, deadheading also helps to extend the flowering period. This is particularly useful for Matthiola plants because, when compared to other flowering annuals, the stock flower has a relatively short blooming period.

Spent blooms can be cut away from the plant with garden scissors as soon as the petals start to wilt. Spent blooms and cut away foliage can be placed on the compost heap.

Common Pests and Diseases

Like many flowering plants, snails and slugs can be a destructive problem, particularly when the plants are young. If slugs are a problem, our guide to getting rid of slugs in your garden has lots of useful tips.

Aphids, flea beetles and cabbage white caterpillars can all target the leaves of the Matthiola plant. Larger pests can either be handpicked or washed from the leaves with a blast from a garden hose.

An application of homemade insecticidal soap can be applied to leaves affected by aphid infestations.

Aphids can sometimes target the plants.

Organic contact insecticides that contain natural pyrethrins can be used to treat flea beetle infestations. These products, while effective, often have a short life span. This means that repeat applications may be required to fully cure the infestation. You can also treat infestations with neem oil.

Infestations of cabbage white caterpillars can be prevented by spraying susceptible plants with a preventative spray. This can be made by infusing six cloves of garlic in water. Alternatively, grow nasturtiums nearby as a sacrificial crop.

Finally, any infected or damaged leaves should be cut away and destroyed.

Many diseases which affect the Matthiola plant, such as verticillium wilt, gray mold, fusarium wilt, leaf spot and root rot are largely caused by overwatering. Easier to prevent than cure, planting in well draining soil and using a soil moisture sensor to monitor the moisture content of your soil are easy steps that help to prevent these issues.

Dividing Perennial Plants

If you are able to grow your Matthiola plants as perennials, the plants can be divided to prolong their lifespan. Regularly dividing perennial plants also helps to keep them productive and healthy.

The process for dividing a stock flower is the same as dividing other perennials. Most perennials require dividing every 3 to 5 years. You can also divide your perennial plants when they become overcrowded.

Perennial plants can be divided in either the spring, just before new growth emerges, or in the fall. Spring and summer flowering plants are best divided in the fall. While most other perennial plants are best divided in the spring some, like daylilies, can be divided at any time of year.

Additionally, some perennial plants dislike having their roots disturbed. These are best divided when they are dormant during the fall and winter months. Dividing sensitive plants when they are dormant helps to reduce the effects of transplant shock.

To divide your perennial plants, use a shovel to dig around the plant and carefully lift the entire clump. Use a sharp knife to slice cleanly through the rootstock. Each section should be a healthy size and have some roots attached.

Following the division of the root system shake away any excess soil and remove any dead growth. The healthy sections can then be replanted in a similar location to the original parent plant.

Companion Planting

The stock flower is a good cottage garden or mixed floral border plant working well with a range of other spring and summer flowering plants. It is also a reliable cut bloom, ideal for inclusion in a cut flower garden.

Nemesia is one of the best stock flower companions. As the stock flower fades, nemesia starts to bloom, filling the gaps left by the Matthiola plants.

Nemesia is a popular companion plant.

Another popular companion plant is the pansy. Both Matthiola plants and pansies tend to bloom and fade at the same time, providing a colorful display. As the plants fade they can be cut back or dug up and replaced with warm season annuals such as petunias and marigolds. Another good combination, particularly if you want a fragrant planting scheme is the sweet pea.

The stock flower is also a good choice for an indoor floral arrangement. This is because Matthiola plants tend to retain their shape and color after harvesting from both the base and root. At its best in a vase, stock flower blooms continue to emit their distinctive fragrance long after cutting.

To get the most out of a cut stock flower remove the bottom leaves from the stems. You also need to remove any leaves that will be underwater or hidden by the vase. Removing these hidden leaves stops the plant from wasting its energy trying to keep them green and healthy. Instead the plant is able to focus its energy on prolonging flowering.

Replace the water in your vases every day. As you do this, snip the bottom of the stems slightly. This stops the stem from sealing up, allowing the plant to continue taking on water. Adding a cut flower feed to the water also helps to prolong the lifespan of the cut plants.

Colorful and fragrant, Matthiola plants are a reliable addition to your planting scheme. Stock Flowers by Harold Litwiler / CC 2.0

Easy to grow, the stock flower reliably blooms from spring to summer if planted in a sunny spot and well draining soil. Regularly watering the plants and deadheading spent blooms helps to prolong flowering.

An attractive, low maintenance specimen, it is easy to see why the Matthiola plant is such a popular member of the floral garden. Now that you know how to care for them, why not add some stock flower plants to your garden?