Dairy of a Greenhouse Garden Part 10: Growing cutting flowers in the Greenhouse

Whilst I was planning the layout of the vegetable garden last year, I introduced a raised bed in which to grow cut flowers, which despite only being planted out quite early was successful. The flowers were all dahlias and gladioli bulbs and required planting directly into the soil as soon as the risk of frost had passed.

This year for Mother’s Day my daughter Olivia gave me a lovely new dahlia called Café au Lait, plus several packets of cut flower seeds. These included, Helichrysum bracteatum, (straw flower), Callistephus chinensis, (China Aster), Phlox drummondii, crème brulee, and Zinnia elegans. These seeds should produce plants in lovely peach and coral shades, and I was wondering if I might be conducting an experiment for potential wedding flowers. There were also some sweet peas, and I was already growing cosmos purity.

It is quite possible to sow flower seeds directly into the garden when the weather is warmer. The advantages of sowing them in the greenhouse is that you can germinate the seeds much earlier on which provides a larger, more mature, and robust plant when it comes to planting out. The protective environment of the greenhouse protects the young plants from frost and from nibbling pests such as slugs. It is easier to control irrigation, so young plants aren’t battered by heavy rain or wither due to drought. The plants should potentially produce flowers much earlier than those sown direct and regular cutting will prolong the season.

I sowed the seeds into trays filled with new compost in early April, and I was pleasantly surprised at how quickly they germinated. I sowed the seeds in weekly intervals, hoping that they wouldn’t all require planting out at the same time, but as they all germinated at different rates that didn’t work. At first, I was watering them very gently with a small watering can, but as they grew larger, I found it much easier to put all the seed trays on the greenhouse floor and give them a good soaking from my large watering can with a rose attachment.

With the miserable and cold early spring we had this year, I hadn’t cracked on with building the new raised beds that I had planned to accommodate all the vegetables I was growing in the green house and now with the new dahlias, (I did buy a few more when they were on sale), I needed to really pull my finger out and get organized.  My dilemma was that with all the cut flower seedlings and the new dahlias I would now need two cut flower beds, plus another bed for growing all the vegetables I had also sown.

So, with help, we built the next raised bed. The posts at the back of the bed in this picture are there to train a grape vine which had to be moved when the greenhouse was first installed. Luckily it was very young and seems to have survived the frost quite well. This bed has been allocated for the flowers. 

We had just enough timber left at this stage to make a mini bed for lettuce.

And six weeks later, it was surprising what a little bit of sunshine could achieve.

There is one more raised bed left to build but that can wait a week or so, as where I had much success with the cut flowers, my vegetables have been rather disappointing. It took three separate attempts to germinate just two courgette plants, and from twelve cucumber seeds, again only two are growing. The tomatoes are doing well though, I had so many plants that I was able to offer them to my neighbours. I placed a notice on the village WhatsApp page, with lots of interest shown, I said they could be collected from our driveway. Unfortunately, before anyone could come and collect them, a car drove up and to my surprise the passenger jumped out and stole the lot.

Text & photos: Sian Napier