Guide to Cut Flowers from A to Z

Guide to Cut Flowers from A to Z


Two of the easiest flowers to grow are Asters and Zinnias, both come in a wide range of bright vibrant colours, will tolerate a wide range of growing conditions and are very forgiving if you happen to miss a day of your usual TLC.

Aster Bouquet

I grew a large bed of Zinnias for a family wedding in early January a few years ago and was rewarded with a fantastic crop. We harvested bucketfuls of long stems for vases and short stems for posies and table-top arrangements. Zinnias can be sown any time from mid-spring through to early autumn, most of them will grow a new stem from where the first ones are cut giving you a secondary harvest of shorter stems.


Asters have a multi-branching habit so reward you with big bushy stems or lots of short colourful ones. They prefer to flower when the day length is descending so don’t start sowing them till after early December and then successively through to late February. A good growing tip for Asters is not to grow them in the same ground every year to avoid stunting - with Zinnias it doesn’t matter so much.

Aster Flowers

Most annual flowers take as little as 75 to 90 days from sowing the seed to when you can cut them. Zinnias usually take 75 days and Asters 90 days so it's all a matter of timing for when you’re wanting to harvest them.

There’s nothing worse when growing for a special day and not having flowers mature enough to pick so plan on having 2 consecutive sowings. If they typically take 90 days from sowing to cutting, sow half your allotted space 105 days out then the other half at 90 days. It's better to have the flowers a little bit over ripe than have them underdone on the day. The same goes for the faster growing ones, sow half at 90 days and the balance at 75 days.

Zinnia Flowers

Start by selecting protected sunny spots in your garden that have good ventilation and well drained soil, this will help you minimize disease problems.

Prepare your ground by digging in plenty of well rotted mulch to assist your plants to develop deep roots and improve drainage while still allowing for moisture retention in the soil.

Always use a good quality seed raising mix, like a good cook, you’ll never achieve the best result by using poor quality ingredients. We prefer Daltons Seed Raising Mix, it's very consistent and reasonably priced.


Sowing your seed into trays and then transplanting or pricking it out at the first true leaf stage, gives you more control and the seedlings a better chance of life.

Seedlings are at their most vulnerable to slugs, snails, birds and damping off at this early stage.

In most cases allow for a spacing of 15-20cm for seedlings that develop into single stem upright plants like Antirrhinum, Aster, Linaria, Scabiosa and Zinnia.

Sunflowers have quite big leaves so need a bit more space, the further apart they are, the bigger the flower head you get as well.

For plants that form a rosette before producing multiple branches from the ground, give them 30cm spacings - Calendula, Cosmos, Cornflower, Didiscus, Marigold, Orlaya, Phlox, Statice and Sweet William.

Keep well watered during the early stages of the plant's growth, an evening water will allow them to soak it up during the cool night before the hot day's sun evaporates it all.

Consider using some form of mesh or stakes and string to encourage the flower stems to grow up nice and straight, having bushy plants blow over can be very disappointing.

Zinnia Lime Green

From our range, we can recommend these varieties as making excellent cut flowers:

70 days from sowing to cutting

Calendula Snow Princess and Indian Prince

Cosmos Candy Stripe, Sea Shells, White Gazebo and Xanthos

Linaria Licilia Azure and Licilia Peach

Phlox Blushing Bride

Sunflowers - all of the Pro Cut series and the taller branching types

Zinnia Candy Cane, Giant Lime, Giant Wine, Giant White and Dahlia Flowered Mix.

90 days from sowing to cutting

Antirrhinums Rose and Snowflake

Aster Cut Flower Assortment and all the King Size colours

Cornflower Classic Fantastic, Classic Magic and Classic Artistic mixes

Didiscus Lace Mix

Marigold Kees Orange

Orlaya White Lace

Scabiosa Summer Fruits

Statice Finest Seeker Mix

Sweet William Summer Cutting Mix

Most flowers can be picked when they first start to open as the petals unfurl and the pollen laden anthers are visible. Flowers are best picked in the morning before the heat of the day sets in or again in the evening once it's cooled down. Picking when it's hot means the flowers will quickly dehydrate and wilt greatly reducing their shelf life. Pick your flowers, strip off the lower leaves and stand them in fresh water in a cool place for an hour or so - this will give you a better bloom to work with later on.

Aster in Gardens

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