Planning which flowers to grow

Planning Which Flowers to Grow

In this lesson I'll take you through the different groups of plants you can sow and when, sharing my simple sowing calendar. We'll also consider colour themes, and how you can organise your thoughts to help you get started.

When I'm planning and ordering my seeds, I make a loose planner to lay out everything I'm going to be sowing. It's not day by day, but more what to do in mid-spring, late spring, etc.

I print out little pictures of the plants to help focus my mind and add to the excitement of what I'm growing and what it's going to look like visually.

Then I group the plants by sowing time.

Sowing Calendar

1. February – Perennials

(I'm only sowing first-year-flowering perennials). I sow these in February and plant them quite early on to give them time to mature and flower. These are some of my choices:

• dahlias – species of dahlias such as Dahlia merckii are easy to grow from seed
• hollyhocks (short-lived perennials) – I'm trying 'Halo Apricot'
• pink cow parsley (Chaerophyllum hirsutum 'Roseum')
• large yellow foxglove (Digitalis grandiflora)
• sweet peas (Lathyrus odoratus cultivars) – I sow a few different varieties. You can also sow these in autumn for a head start, as they're hardy.

2. Early March – Hardy Annuals

These are some of my choices:

• sunflowers such as 'Ruby Eclipse' – a multi-branching form that's great for cutting
• Phlox 'Crème Brûlée' – great for cutting and flowers spill over the edge of the pot or border. Lovely flower with a mix of cream, coffee, pink flowers and markings.
• Leonorus sibiricus – looks a bit like a Verbascum, spikes of pale purple flowers, never tried before.
• larkspur 'Misty Lavender' – spires of pale dusky lilac flowers

3. Early March – Direct-Sown Hardy Annuals

These are some of the hardy annuals I'll be sowing straight into the ground, either scattered in borders (try to remember where you've put them!), or sown in drills:

• Californian poppies
• poppy 'Pandora' – marbled flowers in ruby pink and red
• poppy 'Amazing Grey' – a recent introduction that's my favourite, ethereal lavender-grey-blue flowers
• poppy 'Black Magic' – tiny, very dark black flowers
• nasturtiums – really easy to sow direct, I edge my veg beds with them and I'm going to try edging my cut flower bed with them too.

4. Late March – Half-Hardy Annuals

Don't be tempted to sow half-hardies too early, as you don't want them to get too big too quickly. If plants are in pots for too long, the nutrients in the compost run out and they start to decline, so you want to plant them out while they still look completely healthy. Half-hardies are a bit tender so need to be planted out after the last frosts, e.g. end of May or beginning of June in the UK, so the end of March or beginning of April is a good time to sow.

Always keep in mind when plants can be planted out to try to time your sowing. With practice you'll get a feel for how long a plant is going to take to get to maturity – I've found that cosmos for instance germinate very quickly (3-4 days) and grow quickly too. So the end of March, the beginning of April is. A good time to sow the half-hardies.

• Cosmos – I grow 'Purity' and 'Dazzler' for borders. Cosmos are really easy to grow from seed and new varieties are introduced every year. Check the height on the seed packet whether it's a dwarf variety for pots (30-40cm) or a tall variety for borders, growing to about a metre.
• Nicotiana 'Lime Green' – sprays of lime-green flowers that are fantastic for cutting.
• Panicum elegans 'Sprinkles' – a firework-like grass with beads at the end of the frond-like leaves, great for pots and cutting.

5. Early April – Second Batch of Half-Hardy Annuals

These half-hardies flower later in the year so are very useful for end-of-season colour and extending your flowering season. Many will continue flowering until the first frosts so are very valuable additions to the border.

• Rudbeckias – these come in perennial (hardy) and annual (less hardy) forms – I'm growing 'Sahara', which is a mix of dusky colours.
• Dahlia 'Bishop's Children' mix – I've found this one doesn't really produce tubers and is great for growing from seed.
• Snapdragon 'Madame Butterfly Bronze' – beautiful dusky orangey-pink flowers.
• Zinnia pastel mix from Marlston Farm Girl, her own mix.

4. Early June – Biennials

These produce leaves in their first year and flowers in their second year. Biennials usually flower around the end of May and then set seed, so that's the best time to sow them – at the end of May or beginning of June for the following year, to mimic when they'd be doing it naturally:

• native foxglove (Digitalis purpurea)
• wallflowers (Erysimum)
• honesty (Lunaria annua)

Considering What Colours to Grow

When you're planning what to grow, think about the colour schemes you want. You can have a main colour that runs through, but to avoid 'too tasteful' themes that are sometimes too recessive because they're all one colour, think about injecting some brightness into the theme with pops of brighter or different colours.

I'm often drawn to apricot as a main colour scheme but I'll be throwing in different colours as well. For my apricot base, I've chosen:

• snapdragon 'Madame Butterfly Bronze' – luscious orangey-pink flowers on big flower spikes
• verbena 'Nana Compacta Apricot' – a little verbena that's great for containers.

Another colour that's fashionable at the moment is a dusky lavender pink, so I'm growing:

• larkspur 'Misty Lavender', – an annual delphinium with spires of pale dusky lilac flowers
• Chinese forget-me-not 'Mystery Rose' – like a big forget-me-not but with dusky pink flowers.

As well as these colours, I'm also drawn to flowers that have different tones, shades and intensities in them that make them more subtle and give an 'antiquey' feel to the colour.

Putting Something on Paper Will Help You Organise Your Sowing

It's really useful to keep a planner to lay out what you're planning to grow from seed each year. Group your plants into broad sowing timeframes e.g. – early March, late March – to get a plan in place for when to sow. This will help you keep track, especially if you've ordered a lot of seeds.

Further reading

Flower Colour Guide by Taylor and Michael Putnam (Phaidon Press, 2018)

Your Assignment

Think about some of the colour schemes you might like to try. Think of a main colour and then other complementary colours that can add contrast. For example, lime green might complement plum purple. Try thinking of two possible colour schemes for a border and two for pots.

Then look through seed catalogues or browse some seed websites such as Chiltern or Sarah Raven to find plants that would fit into your colour schemes. Note down some of your favourites in the table.

Plant Directory

Alcea rosea 'Halo Apricot' (Halo Series)

Hollyhock 'Halo Apricot'

Herbaceous hardy perennial

Malvaceae

Antirrhinum majus 'Madame Butterfly Bronze'

Snapdragon 'Madame Butterfly Bronze'

Short-lived perennial, grown as an annual

Plantaginaceae

Chaerophyllum hirsutum 'Roseum'

Hairy chervil 'Roseum'

Herbaceous hardy perennial

Apiaceae

Consolida ajacis 'Misty Lavender'

Giant larkspur 'Misty Lavender'

Hardy annual

Ranunculaceae

Cosmos bipinnatus 'Purity', 'Dazzler', 'Rubenza', 'Kiiro'

Mexican aster, cosmea

Half-hardy annual

Asteraceae

Cynoglossum 'Mystery Rose'

Chinese forget-me-not 'Mystery Rose'

Hardy annual or biennial

Boraginaceae

Dahlia australis

Southern dahlia

Tuberous half-hardy perennial

Asteraceae

Dahlia BISHOP'S CHILDREN (mixed)

Dahlia BISHOP'S CHILDREN (mixed)

Tender perennial grown as half-hardy annual

Asteraceae

Dahlia merckii

Merck dahlia

Tuberous half-hardy perennial

Asteraceae

Digitalis grandiflora

Large yellow foxglove

Evergreen hardy perennial

Plantaginaceae

Digitalis purpurea

Common foxglove

Biennial or short-lived hardy perennial

Plantaginaceae

Erysimum species and cultivars

Wallflowers

Evergreen hardy perennials

Brassicaceae

Eschscholzia californica

California poppy

Hardy annual

Papaveraceae

Helianthemum annuum 'Ruby Eclipse'

Sunflower 'Ruby Eclipse'

Half-hardy annual

Asteraceae

Lathyrus odoratus cultivars

Sweet peas

Hardy annuals

Fabaceae

Lomatium columbianum

Columbia desert parsley

Herbaceous perennial

Apiaceae

Leonurus sibiricus

Siberian motherwort

Hardy annual or biennial

Lamiaceae

Lunaria annua

Honesty

Hardy annual or biennial

Brassicaceae

Nicotiana 'Lime Green'

Tobacco flower 'Lime Green'

Short-lived tender perennial, grown as half-hardy annual

Solanaceae

Panicum elegans 'Sprinkles'

Panic grass 'Sprinkles'

Half-hardy annual

Poaceae

Papaver macrostomum 'Black Magic'

Poppy 'Black Magic'

Hardy annual

Papaveraceae

Papaver rhoeas 'Amazing Grey'

Poppy 'Amazing Grey'

Hardy annual

Papaveraceae

Papaver rhoeas 'Pandora'

Poppy 'Pandora'

Hardy annual

Papaveraceae

Phlox drummondii 'Crème Brûlée'

Annual phlox 'Crème Brûlée'

Short-lived perennial grown as half-hardy annual

Polemoniaceae

Rudbeckia hirta SAHARA (mixed)

Black-eyed Susan SAHARA (mixed)

Tender perennial grown as half-hardy annual

Asteraceae

Tropaeolum majus cultivars

Nasturtiums

Hardy annual

Tropaeolaceae

Verbena × hybrida 'Nana Compacta Apricot'

Florist's verbena, garden verbena

Tender perennial grown as half-hardy annual

Verbenaceae

Zinnia MFG (Almost) Perfectly Pastel (mixed)

Common zinnia MFG (Almost) Perfectly Pastel (mixed)

Half-hardy annual

Asteraceae