What is Bolting? – Micheal Kelly from GIY explains
This month is a bit fragmented or me in the garden. Some things I am trying to speed up, like ripening the tomatoes and sage cuttings. Then on the other hand I am trying to slow down the spinach and lettuce to stop them bolting.
I have three types of tomatoes growing, I can’t remember their names but some are bigger than others and they have all been left to do their own thing barring the odd comfrey feed and nipping out a few side shoots. If they don’t start to ripen soon we’ll be eating a lot of green chutney. The lettuce, mustard and spinach on the other hand has no problem maturing. I bought the “cut and come again” type, but maybe I am not doing it properly (I really don’t know if you can do these things wrong) the resulting plants are bolting even before the leaves have had time to mature.
What is Bolting?
I’ll pass you over to Michael Kelly, a freelance journalist, writer for the Irish Independent Lifestyle pages and founder of GIY (Grow It Yourself www.giyireland.com) Ireland to explain.
“Bolting is a horticultural term which refers to vegetable crops that run to seed before their time. The plant is essentially rushing in to procreation mode – trying to spread its seed (by producing flower or seed heads) before it dies. It is a perfectly natural part of the plant’s lifecycle, but unfortunately it usually renders them inedible.”
What causes the problem?
“It is often caused by a cold spell, changes in day length or other stress in the plant such as lack of water. Some plants such as lettuce, rocket and annual spinach are particularly susceptible.”
When does it happen?
“Though bolting occurs as the plant reaches maturity it can happen much earlier. In annual crops this is usually caused by changes in day length but can be worsened by stressed conditions (lack of water etc). In biannual crops it is caused by unsettled weather conditions or a cold spell early in the propagation phase. Cold nights, followed by hot days will also cause it, as will late frosts.”
So how do we minimize the amount of bolting in our veg patch?
“Watering well and regularly is key since dry soil encourages bolting. Delay sowing cold sensitive plants like chard, onions, beetroot until temperatures have risen or raise in modules in a greenhouse and plant out when temperatures are warmer. Succession sowings will help to beat bolting and provide a constant supply of produce. Bolt resistant varieties are specially bred to resist bolting – examples include Boltardy for beetroot. There are also bolt resistant varieties of spinach, onions, carrots and turnips.” Michael concludes.
I’m taking Michael’s advice here and sowing new salad plants every few weeks and it seems to be working as we have had a continuous supply all summer, barring tomatoes of course.
The Runner beans are prolific and are talking the place of mange tout which have all been eaten. The beans are as long as spaghetti and after being put through the slicing machine look great mixed into the pasta. They are the lads favourite vegetable and I can see why, they are soft (when young anyway) and tasty and go with most meals.
Catch the Cabbage Whites
One thing I have to do every morning is play “grab the Cabbage Whites” in the polytunnel. Every day I am removing at least 20 of them as they tap on the plastic and look for somewhere leafy to multiply. They are after the curly Kale and broccoli of course and every day I have to check for the small yellow capsules under the leaves that soon turn into caterpillars. I’m being very lenient on these butterflies and although it’s tempting to kill them I am catching them gently and letting them go outside of the tunnel door. Right into the path of my outdoor brassicas. You have to give them a sporting chance.
There are a couple of sun loving plants mature enough for harvesting to entertain me until the tomatoes are ready. The sweetcorn is full to bursting and this year I have grown my very first chillies. Time for a runner bean and sweetcorn curry I think.