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You may not realise it, but August is a crucial month for preparing your garden for the following spring. With the right selection of seeds and proper care, your garden can burst into life with a vibrant array of colours, sooner, when the warmer months roll around again.
Hardy annuals are perfect flower seeds to sow in August that will help you have colour in your garden sooner next spring and onwards. Sowing in august produces more robust plants that flower earlier, so it is well worth taking the time to get started.
In this post, we'll explore the top 5 seeds to sow in August to ensure a flourishing and vibrant garden come springtime.
The importance sowing seeds in August
Spring in a flower garden is all go go go! With so many seeds to sow and limited space, it's easy to feel a bit overwhelmed. And let's not forget the suspense of waiting to see if they'll germinate!
Each seed has its own little quirks and conditions for germination, and if something's not quite right, it might not grow. It can feel like a bit of a gamble.
But here's a tip: why not get a head start by sowing some seeds in August? Not only will you get flowers earlier, but you'll also have the peace of mind knowing that you've got something growing. It's a great way to dial down the springtime gardening panic.
Choosing the right seeds to sow in August can make all the difference for us flower enthusiasts who can't wait to see our gardens come to life in the spring. So, it's worth taking the time to pick seeds that are just right for your local climate and soil conditions.
What seeds can you sow in August
Any seeds you decide to plant in August need to be tough enough to withstand a winter, so they have to be frost hardy. This narrows down our options to resilient varieties such as hardy annuals, biennials, and perennials.
Perennials are pretty flexible and can usually be sown anytime during the year. And if you've been on top of things, your biennials should have been started before the summer equinox (that's around June 21st). This means we can now focus our attention on the hardy annuals.
As you might guess from their name, hardy annuals are typically frost tolerant. This means they can, in theory, be planted outside and will survive the winter. But do keep in mind your climate – if temperatures regularly drop below -8C, you might need to give them a bit of protection.
August sowing deadline
In my experience, self-sown seeds like Nigella, Cornflower, and Cerinthe Major are tough cookies! They seem to breeze through winter without a hitch if they have found their own place to settle. However, I'll admit, my experiences with sowing seeds in August and then transplanting them have been a bit of a mixed bag.
I usually aim to have the seedlings ready to transplant before the autumn equinox (around September 22nd). This gives them ample time to settle in and develop their roots while the soil's still got a bit of warmth.
But, it's not always smooth sailing. Sometimes, the seedlings just aren't quite ready to be planted out, so will struggle to grow good roots before winter comes. Or, I'll confess, I might just lose track of time and forget to plant them out in time. And again, they miss their window to develop good roots.
If you find you're in the same boat as me, don't worry! Your August-planted seeds can stay in an unheated greenhouse until spring, and they'll be just fine. They won't need much watering – in fact, overwatering can be more of a hazard than a drought over winter, as they might dampen off and rot.
I'm still in the process of figuring out the best use of my time and seeds for autumn sowings. Last year, I planted nearly all of them outside and, sadly, lost the lot, due to excessive wet weather and what appears to be slug and rabbit damage. But the few I kept in the greenhouse survived. The year before, it was the total opposite – the outside seedlings made it, while my indoor seedlings didn't.
In an ideal world, I want them planted outside so they are not taking up valuable greenhouse space in the spring, but at the moment it seems like the best solution is a mix of both to cover all bases until I get reliable results.
If you're feeling a bit unsure, it's totally okay! Sometimes it's better to sprinkle some seeds around and see what happens, rather than aiming for perfection and ending up with nothing planted. You'd be surprised at how eager seeds are to germinate and grow.
Top 5 flower seeds to sow in August
Let's delve into my top 5 flower seeds to sow in August for a vibrant spring garden:
1. Snapdragons
Snapdragons (Antirrhinum) are a popular choice for many flower gardeners due to their mix of colours and unique shape. They are also hardy plants that can survive in a variety of climates.
Snapdragons are very slow germinators and seedling growers, so if these can be started in autumn then this will give you a great boost in spring. Having these slow growers out of the way means you can plant them out sooner in the spring, clearing up some greenhouse space for those tender annuals a bit quicker
2. Larkspur
Larkspur is a tall, graceful plant that blesses us with stunning blues, pinks, or white blooms. It's an excellent pick if you're looking to sprinkle some height and colour into your garden. Plus, they dry really well!
Now, I'll be honest here, these little beauties are my trickiest customers. They are like reluctant teenagers, I don’t want to think about the number of seeds I've wasted trying to coax them into life, and still they resist my best efforts to develop! But I persist because, let's face it, they're absolutely worth it.
These seeds are fans of cold stratifying, so ideally, you'd sow them directly in autumn and let nature do its thing. That approach, however, hasn't quite panned out for me in the damp UK – I suspect the seeds just give up and rot.
Given the challenges these seeds present, I can't help but feel a sense of achievement when I manage to get a good number of them growing in autumn. It definitely makes my winter!
3. Nigella
Nigella, also known as Love-in-a-Mist, is a beautiful plant that produces delicate blue, pink or white flowers and fantastic dried seed heads. It's also a great choice for attracting pollinators to your garden.
Between you and me, I've found that these little beauties do best when I let them self sow. It's a win-win! They're happy, and I get to save some energy.
Sow these in the autumn and you'll have a gorgeous display by spring. Best of all, they'll self sow throughout the season, providing you with a continuous burst of colour. And guess what? You won't have to lift a finger. Enjoy!
4. Sweet Peas
Sweet Peas are a great choice for any gardener. They produce beautiful, fragrant flowers and are relatively easy to care for. Personally, I think there isn’t a month where you can’t sow sweet peas, if in doubt sow sweet peas!
Autumn sown sweet peas produces strong plants that are ready to burst into flower early June, so are well worthwhile growing.
5. Orlaya
Orlaya is a beautiful plant that produces white, lace-like flowers. It's a great choice for adding a touch of elegance to your garden.
Now, growing these seeds can be a bit of a challenge – they often need a touch of cold stratification, much like larkspur. But oh, the feeling of accomplishment you'll get if you manage to germinate them before winter sets in! Then, you can just sit back and let them do their thing in the spring.
Just to be completely honest with you, you could swap these out for the easier-to-grow ammi majus, or even just make use of the wild grown cow parsley that is abundant in hedgerows around the same time that orlaya is in flower. But if you stick with it, orlaya adds a touch more elegance and glamour than its more laid-back counterparts.
The ecological benefits of overwintering
Getting a head start on spring sowing isn’t the only benefit of an August sowing and overwintering. There is new knowledge that there is great benefit in keeping growing roots in the ground. Much like you do with a green manure.
By maintaining a garden with active root systems, we help to protect the soil and promote nutrient cycling. Root systems stabilise the soil, reducing erosion, and support a diverse community of beneficial soil organisms. So, by sowing seeds in August and maintaining active growth through the winter, we're not just planning for a beautiful spring display but also contributing to healthy, fertile soil.
Sowing the right seeds in August is the key to having a vibrant and flourishing garden in the spring, and a healthy garden all year long.
If you want to buy the best seed for hardy annual cut flowers, I sell them in my seed shop, over on Etsy.
Here are some more that you could try:
- Agrostemma (corncockle)
- Ammi majus
- Bells of Ireland
- Cornflowers
- Cerinthe major
- Daucus
- Dill
- Grasses
- Marigolds
- Poppies
- Scabiosa
I hope you have discovered some new flower seeds to sow in August for a vibrant and blooming spring garden. By choosing hardy annuals like Snapdragons, Larkspur, Nigella, Sweet Peas, and Orlaya, you can get a head start on your spring garden and enjoy a burst of colour and life when the warmer months arrive. Remember, sowing in August not only ensures an earlier bloom but also contributes to a healthier garden ecosystem.
A handy tip for your August sowing: use deep seed trays. This saves time and effort by avoiding the need to pot on, giving your seedlings more room to grow strong roots from the start, whilst socialising with their neighbours (did I really say that out loud!). I also try to use peat free compost wherever possible. Some of which are a bit dodgy, and I think in the case of peat free compost you pay for what you get. Silva grow peat free compost always seems to work well for me, when others fail, although it is in on the pricey side.
As the saying goes, “To plant a garden is to believe in tomorrow.” So start believing and get sowing today!
