When planting Pampas grass (zone 7) what do you add to the dirt to make the plumes come out full? I use to live right outside Wilmington NC when I planted my pampas grass there the lady told me what to put in the dirt to makk them have a full plums. I now live in the Mountains of NC and just cant remember what she told me to put in with the dirt. Thank you in advance for your advice. Grace Mason Glmason62@yahoo.com
Certified GKH Gardening Expert
potassium and phosphorus will help with flowering. There are many sources for this. Here are some articles that will help: https://www.gardeningknowhow.com/garden-how-to/soil-fertilizers/using-potash-in-garden.htm
Or you could get some potassium phosphate. This will kill two birds with one stone. Follow all dilution instructions, and never pour directly on the plant.
Pampas grass requires well-draining soil. If you have heavy clay, you'll need to amend it with peat moss or even small pebbles. Don't add fine sand to clay as you might end up with cement. Get the largest granular sand you can find if you choose this route. For large plumes purchase a female plant. Male plants have less showy plumes. There is no secret ingredient. https://www.gardeningknowhow.com/ornamental/foliage/pampas-grass/growing-pampas-grass.htm