PDA

View Full Version : Soil temperatures for grass growth


max2
19th July 2010, 06:27 PM
I see the daffodils are growing and the green stems well and truly on the way up. Does this mean the soil temperature is now warm enough to stimulate new grass growth?

DiDi
19th July 2010, 07:41 PM
Doubt it! Do you get the Counties News delivered? I seem to recall they have soil temperature recorded every week and from memory, it needs to be around 7 degrees. I know my place which is North facing and not frost prone is definitely not growing grass at the moment. Some - but very slow!

SarahM
19th July 2010, 07:57 PM
We strip grazed the front lawn (paddock grass) about 2-3wks ago and there's some regrowth - not a spring flush, but I was still surprised.

I reckon this winter (here anyway) is warmer or milder than past ones. Not sure where to go for statistics though. We've not had many of those howling southern gales with sideways sleet and hail. Just the odd frost and fine day lately.

Saw some daffys growing here too - just the leaves, no flowers yet. Fingers crossed for a mild winter!

GrantK
19th July 2010, 08:53 PM
I reckon this winter (here anyway) is warmer or milder than past ones. Not sure where to go for statistics though.
Our coldest soil temperature so far this year has been 11.1 degrees, and it's currently sitting at 12.9. Last year, the soil temp. bottomed out at 9.7 on July 14, so it looks like we have probably seen the low for this year at 11.1. Making it a milder winter than last year to the tune of 1.4 degrees, so far as soil temp. goes anyway. Our grass is also still growing, albeit slowly.

Shropshire Blue
19th July 2010, 09:07 PM
Back in the UK we use T200 as a basis for when to put on your first N to boost grass growth.

From Jan 1st, (July 1st here), record daily max air temp and add it up till you reach 200 then away you go, so long as ground conditions allow and no heavy rain forecast.

grannie Mary
19th July 2010, 09:42 PM
We need 10 deg C soil temp here for grass to start growing, absolutely no sign of any movement here & probably wont for at least another month brrrrrrrr

bayrose1
19th July 2010, 09:56 PM
I went away for the weekend. When I came home I noticed that the roadside paddock which we let our fatty ewes completely graze out has picked itself up. Growth as such can be expected but the grass certainly greened up. Even taking a walk through a back paddock today and there is growth happening be it slowly [:D]

GrantK
19th July 2010, 11:26 PM
Back in the UK we use T200 as a basis for when to put on your first N to boost grass growth.

From Jan 1st, (July 1st here), record daily max air temp and add it up till you reach 200 then away you go, so long as ground conditions allow and no heavy rain forecast.
My weather station software (Weather Display) uses "Growing Degrees Days" which is where the daily maximum temp. has 10 subtracted from it, and the resulting difference is added to the monthly total, which is then divided by 2 (for some reason). Thus, for the month of July so far, the GDD total is 67.2.

We need 10 deg C soil temp here for grass to start growing, absolutely no sign of any movement here & probably wont for at least another month brrrrrrrr
Yep, 10 degrees seems to be about what is needed for any noticeable grass growth, which I suspect is why my weather software uses that figure as well.

max2
20th July 2010, 05:42 PM
Doubt it! Do you get the Counties News delivered? I seem to recall they have soil temperature recorded every week and from memory, it needs to be around 7 degrees. I know my place which is North facing and not frost prone is definitely not growing grass at the moment. Some - but very slow!

I will have to look again, I hadn't noticed it...

My neighbour says we need ground temps of 5 degrees, and as we have had some lovely weather recently, I wondered if it was enough to keep the soil temp up?

LongRidge
20th July 2010, 06:13 PM
Different grass varieties have different maximums and minimums. With most varieties, if it grows in the hot then it won't grow in the cold.
Fertility has a huge influence on how soon the grass starts and how long it grows for. If the fertility is right for grass then it will start earlier and keep growing longer.

SarahM
20th July 2010, 08:34 PM
Hi - anyone know where I can find soil temperature data? Had a look on net - all I could find was an Environmental Southland site that wouldn't display the graphs. :( BTW the temps for my area averaged 6.5-7 degrees.

I remember when I was young they used to print that sort of data in the paper quite often. Don't remember seeing it lately.

I reckon this winter is more mild than last, but I want some data. I'm trying to predict when the spring flush will happen around here.

GrantK
20th July 2010, 09:12 PM
Hi - anyone know where I can find soil temperature data?
All you need is a thermometer with an external probe, and you can collect the data yourself, as I do.

The standard depth for soil temperature measurement is 100mm below the surface.

This sensor here would do it, for a cost of $38:

http://www.weatherstation.co.nz/0000009d5208a4001/00000099720868b01/iroxct111c.php

edster951
23rd July 2010, 11:00 PM
try the southland demonstration farm data.....interesting reading

http://www.siddc.org.nz/southlanddemofarm/southlanddemofarmweeklydata.html

SarahM
24th July 2010, 01:28 AM
Thanks Eddie - that's now tucked away in my favs for reading tomorrow.