grass problems

[helen l]

I am a keen (new) gardener and living in Spain. This is my first garden here and am starting to get to grips with the problems of watering, or not.
My main problem, at the moment, is that my grass seems to develop dark patches. Is this over or underwatering? Also I have a lot of dead patches. Is this because I'm watering incorrectly?
I sowed the grass in early spring and it has always been very patchy. I keep sowing more seed but it makes no difference.
The ground was used for vegetables previously but is very hard and dries out quickly.
Thanks

[Grey]

When you say dark patches, do you mean parts are a darker green, or some parts die? If they die, do they seem to die in roundish patches?

If it just dies in roundish patches, it could be cinch bugs.

Darker green means better nitrogen in that area.

Black would be a fungus.

Yellowing means not enough nitrogen, or too much ammonia (like if you have a dog whose system is acidic - wherever it does it's number one will harm the grass).

[helen l]

Hi Grey,
Thanks for trying to help.
The dark,almost black, patches appear overnight and usually are away within a few days.
The dead patches are irregular shaped and in different areas. They are not recovering despite extra water.
We don't have a dog and haven't seen one in the garden.

[Newt]

Hi Helen,

I agree with Grey, the black areas sound like fungus. I do have some questions and guesses based on what you've said already. You said, "I sowed the grass in early spring and it has always been very patchy. I keep sowing more seed but it makes no difference. The ground was used for vegetables previously but is very hard and dries out quickly."

I'm wondering if you mixed organic matter such as compost into the soil. From your description of the ground being hard and drying out quickly, I suspect there is a alot of peat moss mixed into the soil. Peat doesn't really have many nutrients and once dry, it's difficult to rewet. It can also form a crust when mixed with clay soil. Ever try and water a houseplant once it's dried out? You probably notice that the water pools on top and takes time to trickle down.

I suspect that the hard crust on top of the soil is why the seed won't germinate. Another reason the seed doesn't germinate could be the temperature. If the outside temps are over 85*F or 30*C, the seed probably won't germinate.

The fact that you are watering alot has probably caused a fungus or two. You don't say what type of grass seed you are using and you are in Spain, so I don't know if you folks use the same type of grass seed as we do. You could look at these sites to see if you can figure out what is going on with the patterns you see in the turf. I get your hardiness zones as 8, 9 and 10.

If I'm correct about the peat moss and the lack of organic matter, then adding compost to the soil will help with the drainage, nutrients and texture. Here in the US you can rent garden tools. If you can rent or borrow a core aerator and then topdress with an inch of compost in the fall when the temperatures cool, that will do alot to help the texture of the soil. Then you could reseed.

In the meantime let's see if we can id what is going on with the brown and black patches.

Newt

[helen l]

Thanks Newt,
I,ll have a look at the websites you recommended.
You're right about the temperature. It is regularly above 30 degrees.
I am currently trying to improve the soil bot my compost isn't ready yet.
I bought horse compost but I didn't work it into the soil. (I've got a lot to Learn)
My previous garden was in Scotland so the difference is immense.
Thanks again
Helen

[Newt]

Helen, you are so very welcome! Let us know what you find when you look at those sites. I'm hoping that those problems are universal and you will be able to id what is happening. Keep in mind that you may have more then one problem.

You sure do get around the globe. I think that's wonderful.

Newt