Quick Fix for Cracks

The quickest, and just as effective fix for most cracks is wood glue. Cracks on the top of the planter will not affect the integrity of the planter.  I have a couple of planters I've dropped, I fixed with wood glue and it is doing fine sitting outside growing basil. 

The second choice is to make a mix of 2 parts Portland cement, 1 part peat moss, both sifted to a fine powder and just a pinch of vermiculite.  Add water very slowly because you want a thick gravy consistency to the mix.  Wet the area to be fixed and then apply a light coating of the mix. Let dry covered in a plastic bag for 24 hrs in a shaded area.

The other alternative is to do nothing if it doesn't bother you seeing a crack, which is really hard to see unless you really look for it. My brother took a planter from me I was going to fix last year, it has a crack at the top, it's been outside since and doing just fine.  I really wanted to keep that planter, too. 

And lastly, you can cut the crack if it is up towards the top of the planter. I use my chicken cutting scissors because they cut through most anything. I bend the cracked part back, cut the area away that is cracked and then, you're done! The area that was cut will hold together without any adverse effects, and you're left with a new look to the planter. 

I'll post pictures, soon, of before and after repairs, or no repairs at all and left alone. You can decide which is the best method for you.