Annuals are plants that complete their full life cycle in one growing season, this means that they germinate from a seed, grow to maturity, flower and then set seed before they die, this usually takes place between Spring and Autumn.
Annuals can be split into two categories, hardy and tender. Hardy annuals have some ability to survive cold temperatures and frosts, whereas tender annuals are not resistant to cold weather at all.
How many plants to grow for cut flowers.
When you know the space you have, you can work out how many plants you can grow, as a rule, we plant 30 plants per metre sq. This may sound a lot, but remember you are growing flowers for cutting, so want to fit in as many as possible.
Annuals will complete their life cycle in one growing season and will die off in the Autumn. Therefore, they do not need vast amounts of room, and you do not need to allow additional space for them to grow larger and spread the next year. They will be cut down and on the compost pile by November.
As a guide, you have a 3 metre sq bed plus 2 large containers with a combined area of approximately 1 metre sq, this will give you a total of 4 square meters of growing space:
4m2 x 30 plants = 120 plants in total.
You may decide to grow Cosmos (2 Varieties), Cornflowers (1 Variety), Strawflowers (1 Variety), Snap Dragons (2 Varieties), Calendula (1 Variety), Asters (1 Variety), Amaranthus (1 Variety), Statice (1 Variety).
So, choosing 10 varieties, would mean you will be growing 12 plants in each variety. I would sow at least 30% more than you need to allow for failed germination, if they all germinate you will end up with a few more plants than you have allowed for, but you can always gift to friends or family or squeeze them in somewhere in your garden!
Another consideration when deciding how many plants to grow, is the space they will need before they are planted into the ground. When your seedlings are large enough to handle, they may need to be potted on from their seed trays, into larger pots, and they will still need protection from frosts so cannot be left outside without some form of protection.
If you are germinating your seeds inside, you will need to consider where you will put your baby plants when you pot them on. Ideally, they need to be outside in a cold frame or greenhouse, or if you do not have a greenhouse, a sunny, sheltered spot in the garden.
Make sure you cover them up with a thick layer of gardeners fleece at night, especially when temperatures are low, or frost is forecast.
If space is a problem, you could always sow seeds later in the season. Seeds sown in late April could be planted out straight from the seed trays in late May as nights should be warmer and the last frost date will have passed. This avoids the need to pot on and protect, you can even direct sow, this is the ultimate time and space saving method.
How and when to sow your annuals for lots of cut flowers this summer.
Spring sowing.
Plants need light to grow, most plants need 12 to 16 hours of good quality light to put on good, strong growth.
Sowing seeds too early in the season can result in poor germination rates and poor, leggy growth on any seeds that do germinate.
A good time to start sowing your annual seeds is from mid February, around that time we hit 10 hours of daylight, the dark days of winter recede and light level increase. Seeds sown now will germinate 2 to 3 weeks later so will emerge as the daylight hours are reaching 12 to 14 hours per day which is perfect to get them off to a good start.
Starting seeds too early can set you back, seeds sown too soon can suffer from pre or post emergence damping off due to the low light conditions.
Sow your seeds in good quality peat free compost, into robust seed trays that you can use again, preferably with lids to help germination and to protect from mice and slugs. Follow the instructions on your packet of seeds as some species require different conditions. Most seeds need a thin covering of compost however some need light to germinate so should not be covered, as a general rule it is always best to check your packet.
We use trays measuring 15 x 30cm with 24 sections, if possible, sow 2 seeds in each compartment, this allows for germination failure.
Autumn sowing.
If you have some experience and would like to try and have your flowers a month or so earlier, you can sow hardy annuals in early autumn. They will germinate quickly and by the time winter sets in you will have decent size seedlings.
The benefit of sowing in autumn is that the plantlets, grow a good root system over winter, so by the time spring comes, you have small plants ready to plant out and they will grow on quickly, giving you flowers a month or so earlier than their spring sown counterparts.
The downside to autumn sowing of hardy annuals is that they need a fair amount of looking after over the winter, they will need to be kept in a greenhouse and despite being hardy they will need to be given additional protection (using garden fleece) from prolonged cold spells and hard frosts.
They can also suffer from damping off disease, which is brought about by the low light levels and cold and damp conditions of winter. Pre emergence damping off means the seeds rots and does not germinate, post emergence damping off causes the seedling to collapse, usually low down the stem.
This all means that Autumn sown hardy annuals can be quite labour intensive. We do sow some hardy annuals in autumn, but they need a fair bit of mollycoddling to get them through the winter.
The simplest sowing method to adopt, is to sow all your annuals in spring, sow your hardy annuals in early spring, and your tender annuals a little later, this can be a lot easier to manage.
It is worth mentioning that all your spring sown annuals, will need frost protection if cold temperatures and frosts are forecast during spring, this is especially true for your tender annuals, so you will need to consider how you can accommodate them in the period from germination to planting out.
A note on sweet peas.
Sweet Peas grow tap roots (a large central root) so benefit from deeper, root trainer pots the benefit of using these (as well as having healthier seedlings), is that you can usually avoid having to pot the seedlings on before planting out.
Because the pots are deeper the roots have more room so can sit happily in their pots for longer. Sweet Peas sown in Spring can be planted out straight from their root training pots.
Annuals Timeline.
From mid-February you can begin sowing some of your hardy annual seeds, such as sweet peas. From March onwards start your tender annuals seeds.
During April and May, you can sow a 2nd crop of your favourite annual seeds and pot on your first crop. After a period of hardening off hardy annuals could be planted out in April and May but remember to cover with fleece at night if frosts are forecast.
From the end of May and into early June the last frost dates should have passed so you can plant out all your tender annual plants.
September – if you wish to try and overwinter some hardy annuals, September is the month to sow your seeds.
Pinching out annuals.
To pinch or not to pinch? As your seedlings grow, some plant species can benefit from pinching out, this simply means pinching or cutting off the growing tip.
Plants which naturally branch out and produce flowers from each side shoot can benefit from pinching out, some examples are Sweet Peas, Cosmos, and Snap Dragons.
To pinch out, wait until the plant has formed two strong pairs of true leaves and then simply cut the growing tip above the second pair. This will encourage side shoots to form and grow, so you are increasing the number of flowering stems and therefore the number of flowers.
We always pinch our Sweet Peas, when they have two pairs of true leaves, we snip the growing tips off and within days the side shoots lower down the stem start to sprout. Sometimes I even double pinch, snipping off the growing tips of the side shoots when they have two pairs of true leaves, causing more side shoots to form.
Plants which only flower on a central stem, such as stocks should never be pinched out as by cutting off the central stem you are removing the only flowering shoot.
As a general rule, always check before you pinch!
Succession sowing for annuals.
Here at Birch Farm, we grow two or sometimes three crops of our annual flowers. Succession sowing simply means sowing seeds of the same variety a number of times in a season.
For example, we sow our first crop of Sweet Peas in late Sept, our second crop in Feb and we will probably sow a third in March. This ensures we have Sweet Peas from late May through to late Summer.
So, if you have a favourite flower that you want to harvest often all season long, it is worth sowing a first crop in early Spring (Feb to March) and a second crop in April to May.
Types of Annuals to grow.
Choose flowers that are well known for their “cut and come again” ability, this simply means the more you cut the more flowers they will produce. The sole aim of an annual plant is to produce flowers for pollination and then to set seed. When mature, the seeds will fall to the ground and lie dormant over winter germinating next Spring, thus ensuring the continuation of the species.
When you cut the flowers, you are interrupting that process, so the plant is prompted to produce more flowers to complete its life cycle.
Here are our top 10 choices for easy to grow annuals which are also great for cutting (and some for drying too).
A = tender annual, sensitive to cold and frost HA = hardy annual, can tolerate some cold and mild frost
Statice (A).
Statice, scientifically known as Limonium, is a versatile plant prized for its long-lasting, papery blooms and attractive foliage.
Native to coastal regions of Europe and Asia, statice has become a popular ornamental plant worldwide, valued for its ability to thrive in a variety of climates and soil conditions.
Statice plants typically form compact mounds of lance-shaped leaves from which tall, sturdy stems emerge, bearing clusters of small, densely packed flowers.
These blooms come in an array of colours, including shades of blue, purple, pink, yellow, and white, and maintain their vibrant hues even when dried, making them prized for use in dried floral arrangements and crafts.
Statice is also valued for its ability to attract beneficial pollinators like bees and butterflies to the garden.
Plant out after last frosts. Cut the stems when 50% of the flowers have opened, do not cut too early as the stems will be tender and will wilt. Check how firm the stem feels before cutting.
· Pinch – not required.
· Flowering – July to first frosts.
· Germination - Statice seeds are typically sown indoors 6 to 8 weeks before the last expected frost date in your area. You can also sow them directly outdoors after the last frost date. Sprinkle the statice seeds lightly over the soil surface. Press them gently into the soil, but do not bury them too deeply as statice seeds require light to germinate.
Statice seeds typically germinate within 2 to 3 weeks under optimal conditions. Be patient and keep the soil consistently moist during this time. Once the seedlings have developed several true leaves, they can be transplanted into larger pots or into the garden.
Sweet Peas (HA).
Sweet peas, scientifically known as Lathyrus odoratus, are beloved annual climbing plants cherished for their delicate and fragrant blossoms. Native to the Mediterranean region, these vines are a staple in gardens around the world.
Sweet peas are renowned for their abundance of colourful flowers that come in an array of hues, including shades of pink, purple, blue, white, and red.
Sweet pea vines feature tendrils that allow them to climb and scramble, reaching heights of up to 6 to 8 feet so good support is essential.
These plants prefer cool weather and thrive in fertile, well-draining soil with full sun to partial shade. Regular deadheading of spent blooms promotes continuous flowering throughout the growing season.
Sweet Peas grow tap roots (a large central root) so benefit from deeper, root trainer pots. The benefit of using these (as well as having healthier seedlings), is that you can usually avoid having to pot the seedlings on before planting out.
Because the pots are deeper the roots have more room so can sit happily in their pots for longer, Sweet Peas sown in Spring can be planted out straight from their root training pots.
· Pinch – Yes pinch out when two pairs of true leaves are present.
· Flowering - May to July
· Germination – Sweet peas are generally considered easy to germinate. They have a relatively high germination rate under the right conditions, sow them in deep pots to accommodate their long tap roots, cover lightly with compost, place in a bright, warm spot and keep compost moist (but not too wet).
Cosmos (A).
Cosmos are one of those effortless flowers that bring so much joy for so little effort. With their delicate, daisy-like blooms and feathery foliage, they add a lightness and charm to any garden. Native to Mexico and parts of North and South America, they thrive in all sorts of soil and are wonderfully resilient, handling heat and dry spells with ease.
They come in a beautiful range of colours—soft whites and pinks, rich crimsons, and deep purples—and their airy, fern-like leaves provide the perfect contrast. Growing up to 4 feet tall, they sway gently in the breeze, filling borders and beds with movement and colour. They’re also magnets for pollinators, drawing in bees and butterflies with their nectar-rich blooms.
Cosmos are brilliant for cutting, too. They’re what’s known as a ‘cut and come again’ flower, meaning the more you pick, the more they produce. To keep them coming, cut the blooms just as they open, before the pollinators get to them. Once pollinated, they’ll start to drop their petals, so harvesting at the half-open stage ensures they continue to open beautifully in the vase.
Sow them after the last frost, and before long, you’ll have armfuls of delicate, airy blooms to enjoy in the garden and indoors.
· Pinch – yes will encourage side shoots.
· Flowering – June to first frosts
· Germination – Cosmos benefit from a little warmth for germination but generally they germinate easily and quickly.
Calendula (HA).
Calendula, also known as pot marigold, is a bright and cheerful annual or perennial flowering plant prized for its vibrant blooms and medicinal properties.
Native to the Mediterranean region, calendula has been cultivated for centuries for its culinary, medicinal, and ornamental uses.
The plant features distinctive daisy-like flowers with colourful petals that range from sunny yellows and oranges to creamy whites.
Calendula blooms profusely throughout the growing season, attracting beneficial pollinators like bees and butterflies to the garden.
Beyond its aesthetic appeal, calendula has long been used in herbal medicine for its anti-inflammatory, antiseptic, and skin-healing properties.
Its flowers and leaves are commonly infused into oils, salves, and creams for various skin conditions, including cuts, bruises, and rashes.
With its vibrant blooms, easy cultivation, and versatile medicinal uses, calendula remains a cherished plant in gardens and herbal medicine practices worldwide.
· Pinch – not required.
· Flowering – July to September
· Germination – Calendula benefit from a little warmth for germination but generally they germinate easily and quickly.
Amaranthus (A).
Amaranthus plants, commonly referred to as amaranths, are versatile and striking annuals known for their vibrant foliage and unique flower spikes.
Belonging to the Amaranthaceae family, these plants originate from various regions around the world and have been cultivated for thousands of years for both their ornamental and edible qualities.
Amaranth plants exhibit a wide range of growth habits, from upright and bushy to trailing or cascading forms.
Their leaves can be variously coloured, including shades of green, red, purple, and even variegated patterns.
Amaranth flowers are clustered in dense, elongated spikes, and come in hues of red, pink, purple, or greenish white, depending on the species and variety.
Beyond their aesthetic appeal, amaranth plants are also valued for their nutritious and gluten-free edible seeds, which are rich in protein, fibre, and essential amino acids.
Whether grown for their striking appearance in ornamental gardens or for their nutritional benefits in edible landscapes, amaranth plants add beauty and utility to diverse gardening spaces.
· Pinch – Yes
· Flowering – July onwards
· Germination – Amaranthus benefit from a little warmth for germination but generally they germinate easily and quickly.
Helichrysum (A).
Helichrysum, also known as strawflower or everlasting flower, is a versatile and attractive flowering plant prized for its papery blooms and long-lasting beauty.
Native to dry, sunny regions of Africa, Asia, and Australia, helichrysum has become popular in gardens worldwide for its drought tolerance and ability to thrive in poor soil conditions.
Helichrysum blooms come in a range of colours, including shades of yellow, orange, red, pink, and white, and their papery texture makes them excellent candidates for drying and using in crafts or floral arrangements.
These flowers are also attractive to pollinators like butterflies and bees, adding to their garden appeal. Helichrysum prefers well-drained soil and full sun, making it an ideal choice for rock gardens, borders, and containers.
Plant out after first frosts. Strawflowers close overnight and when it is wet, so pick flowers on warm, dry mornings.
Choose blooms which are not too open, especially for drying as they continue to develop when cut and during the drying process so can become overblown.
· Pinch – Yes
· Flowering- July until first frosts
· Germination– Helichrysum benefit from a little warmth for germination but generally they germinate easily and quickly.
Snap Dragons (HA).
Snapdragons (Antirrhinum) are one of those classic cottage garden flowers that never go out of style. Their unique, dragon-shaped blooms add a touch of whimsy to beds, borders, and containers, and they flower for months if you keep picking them.
Native to rocky areas of Europe, North Africa, and North America, snapdragons have been grown for centuries for their beauty and reliability. Their tall, upright stems are packed with tubular flowers that open gradually from the bottom to the top of the spike, giving a long-lasting display from summer well into autumn.
They come in just about every colour—soft pastels, rich jewel tones, and even striking bi-colours—so there’s something for every garden. Snapdragons thrive in well-drained soil and full sun to partial shade, and while they’re easy to grow, they do benefit from regular cutting to keep them blooming.
Growing Notes:•
Pinch? Yes—this encourages strong, bushy growth and more flowers.•
Flowering period: July onwards.•
Germination: Can be slow and patchy, so sow more than you need.•
Top tip: Snapdragons need light to germinate, so don’t cover the seeds—just press them gently into the surface of the soil. Keep the compost moist but not waterlogged, and be patient; germination can take 10-14 days, sometimes longer.
Once they get going, snapdragons are brilliant cut flowers, and the more you pick, the more they’ll bloom.
Asters (A).
Asters
Asters are one of those flowers that quietly wait their turn and then put on the most spectacular late-season show. Their beautiful, pom-pom-like blooms come in shades of blue, purple, pink, blush, and white, adding colour to the garden just as summer starts to fade.
Native to North America, Europe, and Asia, asters are a great choice for extending the flowering season into autumn. They grow in bushy clumps, usually between one and three feet tall, with lush foliage that sets off their abundant blooms beautifully. They thrive in well-drained soil and enjoy full sun to partial shade, making them a versatile option for borders, rock gardens, and mixed beds.
Asters are also brilliant for wildlife, attracting plenty of bees and butterflies when other nectar sources are starting to dwindle.
Growing Notes:•
Pinch? Not required.•
Flowering period: August until the first frosts.•
Germination: Asters germinate easily but appreciate a little warmth.•
Top tip: Don’t be tempted to sow too early—waiting until April means they’ll benefit from longer daylight hours. Plant out after the last frosts.
If you're looking for a flower that keeps going when everything else is slowing down, asters are a perfect choice.
Phlox (A)
Annual phlox (Phlox drummondii) is a brilliant little flower that brings masses of colour to the garden. With its delicate, star-shaped blooms in shades of pink, red, purple, blue, and white, it’s an easy way to add brightness to beds, borders, and containers.
Native to North America, phlox is a reliable and long-flowering addition to the cutting garden, attracting bees and butterflies throughout the summer. It thrives in well-drained soil and a sunny spot and doesn’t need much fussing over to put on a good show.
For cut flowers, pick as soon as the first flowers start to open—phlox is delicate, so handle with care.
Growing Notes:•
Pinch? Not required.•
Flowering period: June onwards.•
Germination: Some varieties need darkness to germinate, so check the instructions on your seed packet.
A simple, cheerful flower that keeps blooming for months—well worth a spot in any garden.
Stocks (HA).
Stocks are one of the most beautifully scented flowers you can grow, filling the garden with their sweet, spicy fragrance. With tall, elegant spikes covered in delicate blooms, they bring a touch of old-fashioned charm to beds, borders, and cutting gardens.
Originally from the Mediterranean, stocks thrive in well-drained soil and a sunny spot, though they can tolerate a bit of shade. Their flowers come in soft shades of pink, purple, white, and yellow, and they bloom from late spring into early summer, attracting bees and butterflies along the way.
If you’re growing them for cutting, stocks are an excellent choice. Their scent is incredible, and they last well in a vase. Just remember—not to pinch them out, as they only flower from the central stem.
Growing Notes:• Pinch? No – stocks only flower from the main shoot, so leave them be.•
Flowering period: June to July.•
Germination: Easy to germinate in the right conditions—typically within 7 to 14 days with warmth and moisture.
If you love scented flowers, stocks are well worth growing. Whether in the garden or in a vase, their fragrance is a real joy.
More annual flowers to consider.
We also grow a wide selection of the following flowers, so you may want to consider including some of these in your cutting patch.
· Larkspur (HA)
· Zinnia (A)
· Daucus (HA)
· Rudbeckia hirta (A)
· Scabiosa (A)
· Florists dill (A)
· Ammi Majus (HA)
· Cornflowers (HA)
· Nigella (HA)
All of the above species have lots of varieties to choose from in a vast array of colours.
They are all simple to grow, germinate well and will reward you with flowers for several weeks if you cut from them regularly.
The best species for easy drying are, Helichrysum, Larkspur, Statice, Nigella and Amaranthus.
When choosing your flowers, the key thing is to look at which variety you would like to grow, as it is the variety that defines the “look” of the flower, the colour, size and shape.
We recommend the following seed companies, Chiltern Seeds, Higgledy Garden and Plants of Distinction, all have an excellent range and supply good quality, fresh seeds.
A note on plant taxonomy
When choosing plants to grow it can be very confusing when Latin names are used. They are used to avoid confusion between common names which can vary so much from region to region.
When you are ordering seeds, the first name you see will be the Genus that the flower belongs to, the next name will be the Species and the final name will be the Variety, for example.
Cosmos - Bippinatus - Daydream
Genus - Species - Variety
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