Question
QUESTION: I hope your experience covers this. Lowe's didn't have but one large purple fountain grass (pennisetum) when I really wanted two smaller ones for pots on either side of my porch. I got the large one. Can I safely divide it without doing damage to it? I will be gentle. I know they're tough plants. Wish they didn't die out in winter, though! I couldn't shop anywhere else because I was using a gift card. Any suggestions at all? I appreciate it. These are some of my favorite grasses- the purple fronds are just breathtaking, don't you think?
Thanks in advance.

ANSWER: Your Pennisetum setaceum is a perennial ornamental Fountain Grass hybrid, sold in some venues (like Burpee) as an annual. In fact, it is a warm-season grass.  Heat-loving and drought-tolerant, it grows in dense clumps and thrives in warmth.

The Floridata website adds this contribution: 'Fountain grass grows in dense, symmetrical clumps that can get 3-4 ft (0.9-1.2 m) tall and 2-3 ft (0.6-0.9 m) across with a fountain of feathery plumes flowing out of the foliage.'

If you are experienced with dividing plants, you will have no trouble with this specimen.  In fact, here's what the people in Florida say about dividing: 'Most of the cultivars do not produce seeds; they are propagated by dividing the root clumps.'

Sounds like a no-brainer to me.

Alternately, you can allow the grasses to go to seed, then harvest the seeds and save for spring.  Results should be interesting.  They may or may not grow true.  This is not for everyone, of course.

Thank you for writing,

THE LONG ISLAND GARDENER

---------- FOLLOW-UP ----------

QUESTION: I forgot to tell you that I live in Zone 7B, middle NC. I learned last year that they just do not over-winter well. I tried keeping one inside with plenty of sun, and that didn't work either. Your suggestion to let it go to seed, the collect the seeds to plant in spring interested me. Might I ask how to tell if they have "gone to seed" and how to collect the seeds? And the how to plant them? Thank you again.

Answer
In a perfect world, all flowers finish blooming and invest enormous sums into generating seeds. You would let them dry on the plant.  Then when they look completely spent and ready, you would simply remove all the seeds.

But in the world we live in, this plant is a challenge.  Because it won't grow true to seed, you see.  Purple Fountain Grass is a hybrid.  Much of the seed you collect is going to be sterile.

You can buy seeds of this plant from many purveyors, including some on the internet. If you grow different colors of Fountain Grass, you may even achieve cross-pollination that will boost results.

FWIW: Fertilizer high in Nitrogen will yield optimal color and encourage flowering, which will get you prettier grass and more seeds.  

THE LONG ISLAND GARDENER