Cold spell coming up... Which of these need protecting?

[Russel Sprout]

Hi all

I'm getting a bit nervous about this upcoming cold spell! I'm in North Norfolk and they are predicting lows of 2 - 3C overnight, as well as potential sleet and hail. I've moved all the pots I can into the shed, but there's a few other bits I'm not too sure what to do with. Everything has been a rush this last month or two (first proper year of gardening) and so I have not got around to getting any horticultural fleece yet

Partly so that I know whether I need to relax or stay up all night worrying, and partly to find out what else I can do to help my plants, I wondered if anyone could offer advice on the following with regards the upcoming weather....

- Apple and Pear trees. 3 year olds but quite small. Most are in flower.

- Strawberries, in the ground - not pots. About a quarter of them have flowers.

- Onion sets - only put out yesterday!

Seeds - only recently sown - of:

- Leaf beet, chard, spinach, radish, rocket... Most aren't showing yet and those that are are VERY small.

- Rasberries, tayberries and wineberries.

Which of these need help and which will be ok? And of those that need help, any thoughts on what I can do? I'm happy going out with my head torch on!

Many thanks, and wishing you all a non-destructive cold spell

Max

[Penellype]

Definitely the strawberries. Any flowers that get frosted will go black in the centre and won't develop into fruit.

Apple and pear trees could do with protecting, but not if the protection is going to thrash about in the wind - its a really tricky one tonight.

The rest will probably be ok unless it drops well below freezing.

[Russel Sprout]

Thanks Penellype. I think you are right RE the trees.... I don't think I can do anything for them that might not end up doing more damage than the potential frost.

Great to hear that the other stuff should - on the whole - be ok. It's only supposed to get down to 2-3C so nothing below freezing. The strawberries though... I'm half tempted to nip out and put a bit of bubblewrap over the ones that have flowers...

Just to clarify, is it just the frost that causes damage? If it gets pretty cold but without a frost, will the flowers on the trees and strawberries be ok? The strawberries are actually on a bit of a slope and there is some hawthorn above them. Might both these things help keep the frost off???

Thanks again

[Penellype]

Yes it is the frost that causes damage, but its the temperature on the surface of the leaf or flower, not the temperature of the air. So an air temperature of 2-3 degrees can cause ground frost, while not qualifying as an air frost. Cold air sinks, so it is always colder on the ground - a slope will help the cold air drain away. The hedge may act as a wind break depending on where it is relative to the wind direction.

My policy is it is better to be safe than sorry. Last night our forecast air temperature was 1 degree, but the actual temperature fell to -0.4. That would be cold enough to damage unprotected strawberry flowers.

There is also wind chill which cools surfaces further. Last night and tonight have significant windchill so the actual temperature felt would be several degrees colder, depending on the strength of the wind.

[Russel Sprout]

That's all very helpful info and helps me to get my head around what's going on and what's relevant. Many thanks.

[Russel Sprout]

Hi

A quick update to say that everything has survived fine, so far... I bought some fleece yesterday. It was too windy to use around the trees, and I'm too new and clumsy, without potentially causing more damage than the weather might, But the strawberries got covered and seem happy.

Vulnerable pots went into the shed....

I covered my chard/spinach/leaf beat seedlings (and seeds - some of them have not germinated yet). Don't know if that was necessary and whether i should bother again tonight? Will read up on their hardiness now, but if anyone can confirm that they will be ok in frost and hail, I'll leave them be...

Huge thanks for all the help with this.

[Russel Sprout]

Oh, and I nearly forgot! Aside form the chard/spinach/beet question...

I recently planted some potatoes and jerusalem artichokes into those plastic grow bag sacks you can buy. Nothing has come up yet (only did it in the last couple of weeks or so). Do they need protecting, or are they only vulnerable when there is foliage?

Ta

[Jungle Jane]

They seem more carefree about losing flowers over at that forum. If you have potato leaves showing & a frosts forecast,I don't cover my potato leaves with compost like someone over there said,I put a long plastic cloche over the top of the leaves & it protects them until morning.
Cold spell coming up... Which of these need protecting? - gardening forum | gardenersworld.com

[TrixC]

Soil is very insulating, so I wouldn't worry about anything that hadn't put up shoots yet. Similarly, if seeds haven't germinated they'll be fine and will just wait for better weather. If some of them have germinated and formed tiny seedlings they will be more vulnerable and could be covered.