Hello there, I have written this guide to help those folk who haven’t grown flowers from seed before. The seeds we use at Higgledy are all annuals, and annuals generally fall into either half hardy or hardy annuals….
Hardy Annuals.
Hardy annuals are flowers which are sown, flower and die within one year and can withstand frost as opposed to half hardy annuals. Some of them are super robust and can be sown straight into the ground in autumn and will soldier on through the winter without protection. Others may need some horticultural fleece to get them through the coldest and frostiest of the short winter days.
Why sow hardy annuals in autumn?
The main benefit of sowing your hardy annuals in Autumn is that you will get a stronger and more abundant plant. It will also flower several weeks earlier than its spring sown chums. Although you may not see much growth above the ground, underneath it is forming a large root structure which will allow it a massive head start come the warmer weather.
When should I sow my hardy annuals?
I sow about half in or around September and half in Spring…March and April, but you can sow in February if you are inclined.
How should I prepare my soil for hardy annuals?
Make things as easy as you can for your seeds. Like most of us they want an easy life. Get your soil to a fine consistency with no bits bigger than a dice if you can. These heroic seeds need to be pushing down through organic matter so best if it isn’t as hard as Kryptonite. Also well tilled soil will have better drainage and the seeds are less likely to drown or rot.
If the ground is heavy clay, then add some barrows of compost and dig in well; it won’t take as long as you think and the results will be well worth the effort.
How do I sow hardy annuals?
For the vast majority of hardy annual seeds I sow them at spacings of about 5 cm and about half a cm deep, but CHECK the seed packet as some seeds need light to germinate). I score a line in my well prepared bed with the handle end of my rake, pop in the seed as close as I can to my 5cm target and gently rake over. Gently water the row BEFORE you sow the seed, this prevents the seed from being washed away if you decide to water after sowing.
Leave about 25 cms between your rows.
Take your time over sowing, it may be a little tedious, but care now will save you time later and increase your yield of fine flowers.
I mark my rows with some sand. The sand won’t affect the germination of the seed and allows me to see which bits I can hoe without worrying that I’ll destroy all that I’ve worked for and also makes your neighbours think you know what you’re doing.
Do I need to thin out my hardy annual seedlings?
Indeed you do my horticultural friend. It will feel really wasteful, but I’m afraid you just have to harden up and deal with the pain. Check the packet for spacing distances. I normally thin everything (almost) to about 25cm. I like my plants to offer each other a little support but not outcompete one another.
If you have a second thinning session in spring the plants will be strong enough to be moved elsewhere in your plot.
Do my hardy annuals need staking?
My flower field is reasonably sheltered but I still use some support. I take some pea netting and put a layer of it at about 50 cm off the ground. My beds are a metre wide and the pea netting comes two metres wide…so I cut it to a one metre wide strip and all is well with the world. Some find it necessary to have another layer higher up, I haven’t found this necessary on my plot.
How do I look after my hardy annual seedlings?
The ground MUST be kept moist. If it doesn’t rain on the little Munchkins then you must water twice a week or they shall perish and you will never forgive yourself and your life will be blighted by guilt and despair. (Nice to avoid that if you can.)
Keep them free of weeds. Weeds are thieves, stealing light, minerals and water. Get them gone. If you leave spaces between the rows you can run a hoe through them and make life much easier on yourself. Don’t wait for these weedy criminals to get established, get them whilst they are young. Show no mercy, you mustn’t let chaos prevail.
I use a 5 cm layer of mulch on my beds, it saves you aeons of time weeding and helps keep the moisture in.
Can I sow my hardy annuals in spring?
Yes, you can. You will get slightly smaller plants however. They will be later to flower, which of course can be a great advantage and they will in theory last longer into the season. I tend to sow some in autumn and some in spring.
If all goes well your autumn sown seed will be in flower in Mid May.
What types of hardy annuals will survive a cold winter?
Ones that always seem to survive for me are….
*Cornflowers (These seem to be mega tough…drought…cold…no problem)
*Nigella. (Love in a mist)
Which hardy annuals would require some protection from the cold?
*Sweet peas
*Gypsophila
*Salvia veridis
Have fun planting your hardy annuals. They are well worth the effort and are stalwart chaps to have growing in your garden and should bring you lots of pleasure.
Half hardy annuals
There is some confusion in the gardening world as to what half hardy annuals actually are. So to make it clear….just remember that hardy annuals are twice as hardy as half hardy ones, which in turn are half as hardy again. OK?
Or…half hardy annuals are plants which grow, flower, set seed and die in one year and won’t withstand the winter.
The other difference between them and hardy annuals is that they tend to be more glamorous, a little more exotic. They have a deeper relationship with the sun and this perhaps makes them somewhat racy.
Half Hardys include..
Didiscus
Many sunflowers
When Can I Sow Half Hardy Annuals?
In my neck of the woods the old boys say the last frosts finish by the 15th May. It is imperative that half hardy annuals are not sown outside before this day in our area.
For some plants this would leave too short a growing season and it is for this reason that the seeds should be started off undercover, in a greenhouse or similar.
Many start their seeds off in February. I think this is too early, seeds sown later soon catch up and often the early sown ones have problems: get leggy and/or are a general pain in the bum.
I tend to have a mass sowing session around the beginning of April. This gives the seedlings a full six weeks to get up to my ‘last frost date’ of the 15th May by which stage they will be big enough to handle the outside world and all of it’s horrors.
However, they will need hardening off. This requires you to get them acclimatized to the cooler weather beyond the safe confines of the greenhouse, windowsill or cold-frame. This can be done by leaving them outside during the day and into early evening for ten days or so before bringing them back inside for the night.
How do I sow my half hardy annual seeds?
The secret to this game (please don’t broadcast this) is to use 3inch square pots. “Why so?” I hear you sing in unison. Well my friends…a three inch pot ends up being just the right size for a six week old seedling, any smaller a pot and our chum the seedling will outgrow it and any bigger a pot will just take up more space, more compost and more of your hard earned pennies.
“But Benjamin…why in Bertie’s name do they have to be square?!” Because it’s harder for the bl***dy snails to hide amongst. Line up all your square pots, preferably in a tray with their sides close against each other….there is safety in numbers.
It is worth noting at this point that Zinnia’s hate root disturbance AND they hate the cold….fussy little tykes. Therefore I sow mine a little later so they end up still being fairly small by my last frost day. (15th May) I also harden off the other more macho plants first and leave the Zinnia’s till everything else is planted out.
Some folk like to sow in seed trays and then prick out and pot on. Yawn yawn….why make more work for yourselves? I’ve found germination rates are very high with single seeds in my three inch pots, if germination hasn’t happened after the others are sprouting nicely, I simply pop in another seed. Simples.
I use a standard peat free potting compost. We NEVER use products with peat in…if Kew gardens can avoid peat then so can we.
I cover the trays with a compost bag or thick bin bag to exclude the light until the very first green shoots can be seen. Don’t remove the bag too late as they will all get leggy and it will result in rubbish plants…your neighbours will laugh at you over their avocado and prawn starters and the whole summer will be ruined.
When can I plant out my half hardy seedlings?
Check the weather. The wonderful BBC have a weather site which will tell you if the temperature is likely to drop below freezing. It will be of no surprise to you to know, if it does….don’t put ‘em out. I had a disaster this year, if you’re feeling like having a snigger at my misfortune then please click on FROST DISASTER!
Aftercare of half hardy seedlings
Much like my hardy annuals, I plant out at 25cm apart and water in really well. Let them get their roots right down amongst the action and become established where they will find the ground water.
I use pea netting as support for my plants, some folk don’t. I suggest if your plot is remotely unsheltered then you would be better off with some support. If you want to use your blooms for cut flowers then it is a must as this helps keep the fellas straight.
Can’t I just wait until the frosts have finished and plant my half hardy seeds in the ground?
Most half hardy annuals perform much better with a push start in the greenhouse. Some however will do just fine when sown after the frosts, in the ground where they are to grow. Cosmos seem to be fine with this approach, as do Zinnias, but they will flower a couple of weeks later.
Most importantly, enjoy yourself…plant some too early or too late, see what happens,or perhaps turn them into funny hats and go to the pub for a port and lemon?
Don’t forget…you can always buy flowers off me if yours don’t work out. 
I hope all the information that you need in order to grow your flower seeds is here. There are profiles of each flower and more detailed sowing guides on the Higgledy site. Click on ‘Flower profiles and sowing guides’ which is found in the right hand side bar.
I will be growing all the varieties in our 2012 collection so it would be great to compare notes with you all. Feel free to comment on blog posts as they arrive.
Should you need further help then either email me at contact@higgledygarden.com or ring me on my personal line…07762633888
KIndest regards
Benjamin
January 25, 2012 @ 11:21 am
Thanks – very useful – be even more useful if I could print it!
Cheers
January 25, 2012 @ 11:27 am
Very good point Kate. I shall be getting a PDF sorted and will post a link to it from that. Thank you!
January 29, 2012 @ 6:01 pm
Thanks!