Seasonal check list as autumn arrives
As soon as a particular seasonal comment is made in my horticultural world there is a stream of additional questions to be answered.
On this occasion, round the table with a few chums, the point at issue was what’s to be done with all the green, unripe tomatoes still hanging on the plants!
I set about this very task last week, removing the green fruits before dumping the plants. They were taken off and placed on seed trays which I left sitting on the greenhouse shelf. Each tray was covered with a plastic dome but allowing a small amount of ventilation.
“Aye, but when they are picked too early and ripened like ‘at’ they dinna taste the same – jist like the produce fae the Mediterranean. It’s picked ower early, stuck in special temperature controlled vans for transport thoosans o’ miles!”
That was followed by reminiscences of family life years ago. “I’m sure my Grannie used to put the green tomatoes in a drawer where they would ripen slowly” or “I think my Mother put green tomatoes in a plastic bag with a ripe banana to make them ripen”. There is a bit of truth in the old methods and that’s where the science comes in. The ‘agent’ involved in the process is ethylene gas.
Fruits generate ethylene gas as they ripen. It is a natural plant hormone which speeds up the ripening process. When you put the green tomato fruits in an enclosed space i.e. a linen drawer or some such, the concentration of ethylene will increase and so cause the mature fruits to turn red. It is what we refer to as ripening!
Similarly, putting a ripe banana in a closed poly bag along with unripe tomatoes will ‘do the business’ because the banana will also give off ethylene gas from the skin.
In a wider context, the gas, converted to liquid is used on commercial crops, like bush tomatoes being grown for processing.
Sprayed on at a key stage, all the mature fruits on the plants will ripen at the same time, allowing the crop to be combine harvested. I have used the technique on a commercial glasshouse tomato crop at the end of the season to achieve one last pick before pulling the plants out! It was standard practice at one time.
Another end of season task relates to removing the summer bedding plants whether it be from garden border, baskets, tubs or other containers and the question which many ask is what to do with the exhausted compost from containers.
Annual plants are generally shaken free and consigned to the compost heap. Plants in containers may be treated just the same and the compost from containers retained for further use. Some of you may have seen the Beechgrove Garden visit I made to Carluke to see a garden with begonias, begonias and more begonias – in the ground, in hanging baskets and in huge containers.
“Do you use fresh compost in these huge pots every year?” says I, to which the reply was: “No, I leave most of it in the containers, refreshing it every year with new compost as required. Many of you will be re-planting containers now, with polyanthus, violas, pansies, myosotis, wallflower and bulbs. Be assured that you only need to add enough new compost to make up the levels.”
“Aha, but do I need to empty the containers completely to mix the fresh in with the old compost?” See what I mean, answer one question and it immediately leads to another! The answer is in the affirmative, it allows you to check out the drainage in the bottom AND mix in a handful of slow-release fertiliser such as bone meal before filling the container again.
Finally, yet another regular question – is it OK to save seed from the vegetables and flowers that we grow? Of course it is, many people do this on a regular basis and get a great deal of satisfaction from growing their own for real! Then comes another related question – I tried this two years ago, sowed the seed last year and was very disappointed with the outcome. The plants were just not the same.
The most likely answer to the second question goes like this – success from seed saving will be achieved because the plants in question were from a simple, stable true breeding line. The unsuccessful outcome of the second question resulted from saving seed from plants which carry the F1 suffix. This is a hybrid cross between two different ‘true breeding lines’ and to produce new seeds each year. These original crosses have to be made afresh every time (hence the cost of F1 hybrid seed is dearer). Plants grown from seed taken from F1 hybrid plants are F2s (the second filial generation) when the characteristics become totally muddled!
Unripe tomatoes still hanging on the plant
Begonias, begonias and more begonias
Unripe tomatoes can often be ripened by grouping with fruit that is already ripe