hardland
Senior Member
Posts: 248
Joined: Tue Apr 06, 2010 3:05 pm
Location: Sth Florida

Why does my soil get crusty on top ?

I'm mainly using 20" plastic containers for Tomato and squash plants. Seem to coming along OK, Toms are fruiting, not red yet but fingers crossed. My soil is 1/3 Black cow manure, 1/3 Peat moss, 1/6 Vermiculite and 1/6 Miracle grow organic for vegetables. The soil seems nice and loose, no puddles at first, but after a few weeks the top gets quite crusty. It takes maybe ten seconds for the water to absorb into the soil. Is this normal?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

User avatar
rainbowgardener
Super Green Thumb
Posts: 25303
Joined: Sun Feb 15, 2009 11:04 pm
Location: TN/GA 7b

Not sure, but it could be the peat moss. When peat moss dries out, it can be very hard to wet again -- like putting water on a totally dried out sponge. Try mixing a little bit of topsoil in with your mix and not letting it dry out as much in between waterings.
Twitter account I manage for local Sierra Club: https://twitter.com/CherokeeGroupSC Facebook page I manage for them: https://www.facebook.com/groups/65310596576/ Come and find me and lots of great information, inspiration

User avatar
applestar
Mod
Posts: 27974
Joined: Thu May 01, 2008 11:21 pm
Location: Zone 6, NJ (3/M)4/E ~ 10/M

Maybe it would help if you mulch. Mulching the surface of larger containers also helps to conserve moisture. My favorite is compost or crumbled leaves. I usually have some leaf piles that didn't get picked up or got blown into the corners of the patio and under the patio furniture -- patio gets cleaned up and the container plants get extra mulch :wink: (Be sure to wear gloves -- I almost always find spiders in the leaf piles).

User avatar
soil
Greener Thumb
Posts: 1855
Joined: Fri Jan 23, 2009 1:40 am
Location: N. California

i second the mulch
For all things come from earth, and all things end by becoming earth.

DoubleDogFarm
Super Green Thumb
Posts: 6113
Joined: Mon Mar 29, 2010 3:43 am

I'm also thinking it's the peat. What is in the cow manure :?: Does it also have saw dust or wood chip :?: I third the mulch :lol:

User avatar
SP8
Green Thumb
Posts: 317
Joined: Sun Jul 19, 2009 3:29 am
Location: Nagoya: Japan

In my containers with tomatoes the surface root growth can get extremely thick and cause the water to pool up like you’ve described. What you’ll find is that when this happens the water will soak down at the points of least resistance which more often than not is at the sides of your container and run straight out the bottom without watering the plant (excessive mulching can also cause this).

I’ve got a metal coat hanger which I’ve straightened out which I use to jab a bunch of holes right down to the bottom of the container every now and then. This helps to stop pooling, aerates the roots and ensures the entire root system gets a drink.
I >>used to<< grow vegetables in containers on my balcony and this >>was<< my Blog:
VEGGIE-MIGHT

hardland
Senior Member
Posts: 248
Joined: Tue Apr 06, 2010 3:05 pm
Location: Sth Florida

SP8 wrote:In my containers with tomatoes the surface root growth can get extremely thick and cause the water to pool up like you’ve described. What you’ll find is that when this happens the water will soak down at the points of least resistance which more often than not is at the sides of your container and run straight out the bottom without watering the plant (excessive mulching can also cause this).

I’ve got a metal coat hanger which I’ve straightened out which I use to jab a bunch of holes right down to the bottom of the container every now and then. This helps to stop pooling, aerates the roots and ensures the entire root system gets a drink.
It's funny you mention the surface root growth, lately when I disturb the surface soil, I can see lots of white whispery roots. It kind of surprised me to see them. Maybe this is more likely to be seen in containers ? maybe the roots have no other place to go. I was thinking of adding some more soil to the surface, good or bad idea ? I assume you coat hanger trick will not hurt the roots. Thanks for your input.
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

hardland
Senior Member
Posts: 248
Joined: Tue Apr 06, 2010 3:05 pm
Location: Sth Florida

P.S What size containers do you use?
Hey there Mister,
Can you tell me what happened to the seeds iv'e sown,
can you give me a reason sir, as to why they've never grown,

User avatar
gixxerific
Super Green Thumb
Posts: 5889
Joined: Fri Jun 26, 2009 9:42 pm
Location: Wentzville, MO (Just West oF St. Louis) Zone 5B

I see people asking for mulch as a fixer. Funny thing I was planting onions around a small tree I have and the mulch itself was crusty.

But I second the addition of good soil, preferably compost. Could be it's just to warm. My cool weather plants are bolting due to the steady near 90's we have been having. Keep that area watered but the soil addition will help than GOOD mulch.

User avatar
SP8
Green Thumb
Posts: 317
Joined: Sun Jul 19, 2009 3:29 am
Location: Nagoya: Japan

hardland wrote:P.S What size containers do you use?
Ones in cm..... :lol:

See below for sizes e.g. https://veggie-might-sp8.blogspot.com/2009/08/plot.html
I >>used to<< grow vegetables in containers on my balcony and this >>was<< my Blog:
VEGGIE-MIGHT

imafan26
Mod
Posts: 11392
Joined: Tue Jan 01, 2013 1:32 pm
Location: hawaii, zone 12a 587 ft elev.

Re: Why does my soil get crusty on top ?

If you have clay soil it is probably from impacts of rain on the bare soil. Fine particles of clay aggegate and when they dry they form a hard crust. Usually if you can break through the crust you will find that the texture of the rest of the soil is crumbly.
High salt content can also affect the crustiness of the soil

Although clay should not be worked when it is wet, it is easier to work when it still has some moisture in it and not when it is very dry.

Incorporate lots of organic matter and mix it well into the soil. Gypsum can help reduce crusting sodic soils and make it easier to dig in hard soils

Till in crop residues to increase orgainic matter.
Happy gardening in Hawaii. Gardens are where people grow.

User avatar
Meatburner
Senior Member
Posts: 174
Joined: Sun Jun 17, 2012 6:00 pm
Location: SW MO zone 6b

Re: Why does my soil get crusty on top ?

imafan26, do you have to deal with clay soil in Hawaii?

User avatar
jal_ut
Super Green Thumb
Posts: 7480
Joined: Mon Jan 19, 2009 3:20 am
Location: Northern Utah Zone 5

Re: Why does my soil get crusty on top ?

You say you are growing in soil: My soil is 1/3 Black cow manure, 1/3 Peat moss, 1/6 Vermiculite and 1/6 Miracle grow organic for vegetables

Uh........ none of these things are soil. They are fertilizers or soil additives to lighten up the soil.

Soil, that miraculous thin covering of the earth where plant roots reside, consists of clay, silt, sand, organic matter and a host of micro organisms. Go to a construction company or Ready Mix and get some real soil, then add some of your fertilizers.
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-

ButterflyLady29
Greener Thumb
Posts: 1031
Joined: Tue Oct 20, 2015 1:12 am
Location: central Ohio

Re: Why does my soil get crusty on top ?

It's in containers. Real soil doesn't work in containers.

Peat based mixes get crusty. The best mix I made had coir fiber instead of peat. Some fertilizers can accumulate on the surface and cause a crust too. It wouldn't hurt to mix a little compost into the top of the container every couple weeks. Just add a thin layer and gently scratch it into the crusty surface. Don't go so deep that you disturb the plant roots.

imafan26
Mod
Posts: 11392
Joined: Tue Jan 01, 2013 1:32 pm
Location: hawaii, zone 12a 587 ft elev.

Re: Why does my soil get crusty on top ?

Crusty soil can be caused by rain. It pelts at the soil and washes out the loose stuff on top and compacts the rest. When it dries, it it leaves a thin but very hard crust on top that doesn't even want to let water through. Usually if you break through the top crust the soil below is much looser.

It is a problem especially with clay soils that are high in magnesium and or salts.

I would add more vermiculite to increase the drainage and mulch the container to keep the rain from pelting the soil.
If you have a high salt content in the soil, which can happen if you are using manures which can be high in salts. I would also add mulch on top of the pots so when it does rain, theire are will be fewer impacts.
Happy gardening in Hawaii. Gardens are where people grow.

User avatar
jal_ut
Super Green Thumb
Posts: 7480
Joined: Mon Jan 19, 2009 3:20 am
Location: Northern Utah Zone 5

Re: Why does my soil get crusty on top ?

ButterflyLady29: "t's in containers. Real soil doesn't work in containers. "

Um...... apparently that fake soil doesn't either? My suggestion was: Get some real soil and mix some of those amendments with it. You say it won't work? Well I am here to tell you, it will work. Perhaps you should try it?
Gardening at 5000 feet elevation, zone 4/5 Northern Utah, Frost free from May 25 to September 8 +/-

imafan26
Mod
Posts: 11392
Joined: Tue Jan 01, 2013 1:32 pm
Location: hawaii, zone 12a 587 ft elev.

Re: Why does my soil get crusty on top ?

I have clay soil and I am dealing with the crust now. It is hard to break through since it is also loaded with fibrous roots but mine actually does drain well. It was about 2 inches thick but the soil below was loose and crumbly. Actually it was cloddy because I worked the soil a while ago when it was wet so I am still paying for that mistake. I had to get the pick to get through the crust though, I couldn't even get the shovel point into it.
Happy gardening in Hawaii. Gardens are where people grow.

Return to “Vegetable Gardening Forum”