Spacing between pots – does it matter?
Last year I allowed for room between pots, using spacing guidelines of 45cm to 60 cm where possible. But then a degree of confusion set in – were those recommendations more relevant for plants sharing open ground; where spacing is practiced to control the competition between plants for nutrients, water and root space ?
In pots, whilst space maybe more limited, sharing is not required. So is spacing ? I decided not.
Taking a more back to back pot approach has resulted in a more orderly layout. This makes for quicker watering and with a more sequential layout, pots don’t get missed or watered twice.
But now this article by Alys Fowler has sown the seed of doubt. The reason – poor air circulation. Her recommendation for pots is to give them plenty of space. And if in the ground, planting distance should be 1-1.5 m apart. All to do with blight. Her take on growing tomatoes outside - ’ a big gamble‘……. HELP !!
Last year I bought Bordeaux Mixture but didn’t use it. Feeling like I might’ve had my year of beginner’s luck I’ve now got it out to read the instructions. For potato blight, spray before blight appears, usually late June to mid July. For tomato blight, spray before the disease becomes active, late July to early August. Then every 3 weeks.
But Alys’ article states tomato blight appears from late June onwards.
I’ve been told a good way to know if blight’s arrived is to listen to the Archers. Apparently it gets woven into scripts once it starts making its presence felt in ‘real’ life. But with apologies to devotees its something I can’t do. I’ve tried. I drunk tea out of an ‘Easy Tiger’ mug as its Archer’s significance is explained to me. I’ve tuned in and tried…..and whilst the dimpty, dunkty tune doesn’t have me reaching for the off switch anywhere near as quickly as the musical misery claxon of East Enders, I still can’t go over to the Ambridge side.
So instead I’ve signed myself up to Blight Watch… where Clear and Present Danger takes the form of a Smith Period. Two consecutive days where the temperature is over 10C and the relative humidity 90% plus for a period of 11 hours in each day. These conditions are right for blight.
It’s organised by postcode and it would seem no Smith Periods have occured in my area during the past 14 days. Out of interest I looked back to 2009. The earliest near miss was 9th June. And then actual Smith Period direct hits were 12, 17, and 27th July; 2,7,27 and 31st August. And then 16th September.
I’m also cross referencing to the BBC 5 day forecast which gives humidity readings. For example although heavy rain is forecast tomorrow – the humidity reading is 54%. So would that mean no Smith Period ?
I’ve no idea if I’ve understood any of this correctly but I’m going to keep checking and seeing what correlations there are – and meanwhile thinking what approach I should take re using Bordeaux Mix.
And if Archers fans glean blight news from their listening please share. Or if you’ve successfully beaten blight using Smith Periods in the past it would be great to know more.
And for anyone who hasn’t come across Blight Watch but would like to know more go to blight watch co uk.
{ 3 comments… read them below or add one }
I find that blight strikes when the plants are wet overnight or for a prolonged period, during wet weather. It’s endemic, so IMO you might as well assume that you’ll get it and be ready to take action. Spreading your plants out and removing lower leaves might stop wet leaves touching and spreading it that way.
One advantage you have with pots is that the compost won’t contain any spores, which can survive in soil for years apparently. Another is that plants won’t get splashed by infected rainwater from the ground. I must trim mine back too.
I’ve never used Bordeaux Mixture so can’t comment there. IMO, the best you can do is to keep plants dry and out of the rain, consider rainwater lethal to tomato plants and perhaps use your shed to shelter a few plants if you can. It can’t spread without moisture.
Fingers crossed for a blight-free summer…
Great reassurance on the advantages of pots re compost and rainsplash.
Apart from the risk of blight do you know if there are any other reasons for tomatoes not liking getting their leaves wet ?
Its one of those things I know – and always water in a way they don’t get wetted in the process – but wondered if there were other reasons.
I’ve gone ahead with the Bordeaux Mix but as can tell from today’s post – am not sure it was the right call ! However its done now and trying out new things is good ..?!?
I don’t know any reason, apart from blight, for tomato plants not liking their leaves wet. My plants inevitably get wet leaves while I’m watering, and they haven’t complained yet. I think if they’re constantly wet, other fungal diseases could occur, like damping off. Here’s a brief summary of tomato diseases; sorry if I’m repeating what you already know! But blight’s the biggie in the UK.
I think you’re right to spray the plants with Bordeaux now, it’s a preventative measure after all. Your plants do look unevenly-splodged though; maybe you could use a hand-spray bottle, like those that common cleaning products are sold in. Unsprayed leaves might still be vulnerable.
I’ll be buying some B.M. for my potato plants (same plant family) this weekend, as i can’t really make another shelter.
All I.M.O. of course. Good luck