Living Columns & Blogs

Ask a Gardener: Deal with whitefly; collect poppy seeds now

Every poppy blossom, when the petals wither and fall off, will produce hundreds, if not thousands, of seeds.
Every poppy blossom, when the petals wither and fall off, will produce hundreds, if not thousands, of seeds. Associated Press

Question: We are having a dreadful time with whiteflies in our greenhouse. What can you suggest?

Answer: Whiteflies are one of the top 10 insect pests in the west. They’re somewhat like aphids, as they suck juice out of plants, weakening and even eventually killing them. Also like aphids, the honeydew secreted by whiteflies protects ants from their natural enemies. And the honeydew causes black mold to form, further injuring the plant.

All in all, it’s a nasty problem, though there are several solutions you can try. One is to hang sticky flypaper around the infested plants. This works well to nab the adults. Replace the flypaper regularly, as the stickiness wears off. Another approach is to hang yellow cardboard squares covered with a sticky substance, which you can buy at a nursery. The yellow color attracts the whiteflies, and the sticky material traps them. When covered with whiteflies, you can wash the squares off, recoat them, and use over again and again.

For a heavy infestation, use an insecticidal soap spray. Make sure your greenhouse is well ventilated. Check any plants you bring in, to make sure you aren’t introducing the little critters.

Don’t despair if you see just a few whiteflies; plants can withstand moderate infestations. Whiteflies have many natural predators, and a cold winter will wipe them out.

Above all else, keep on top of the whiteflies. You can solve this problem!

Q: I grew the most gorgeous poppies this year, and everyone, including myself, want to have them next year. How do I do that?

A: It’s simple, and you’ve asked just in time! Every poppy blossom, when the petals wither and fall off, will produce hundreds, if not thousands, of seeds. They are incredibly small and colored jet black, irrespective of the variety of poppy.

Wait until the pods of the plant have turned a brownish color, indicating that they are “ripe.” Carefully cut off the stem, making some effort to keep the pod from dumping all its seeds. You don’t really need to be too careful, because as I mentioned, they are prolific reproducers.

Collect all the seed you can, then, several days later (to make sure they’re completely dry) store it in an airtight container. Keep it out of the sun in a dry and dark place.

It won’t be stored for too long, however. The best time to plant poppy seeds if you want to have their bright blooms in the spring is fall. There’s a problem with the planting, but there’s also a simple solution.

It’s hard to keep track of where you plant these tiny seeds. It’s good to mark the poppy patch so you don’t inadvertently dig up the seeds. Make a hoop out of a pruned branch and label a small terracotta pot. Bend the branch and write “poppies” on the pot, and you’ll not accidently plant something in this spot during the spring planting rush. And as soon as the poppies germinate, the hoop and pot can be removed. Be sure to look through catalogues to find some remarkable new varieties of poppies. They’ll blow your socks off.

Q: I’m trying to compost everything I can to avoid having yard waste, as well as improving my soil. But I end up with a lot of sapling wood that would take too long to compost, and I can’t afford a good chipper. Can you think of a possible solution?

A: Yes, indeed. Nothing makes a veteran gardener happier than not having to spend money on equipment and supplies, but rather to find or make them. An overabundance of sapling wood is a good case in point.

You can make attractive trellises, mask ugly pots, have an ever-ready supply of stakes, and give your vines wonderful structures on which to stretch their limbs.

If you want curves in what you’re building, you’ll do best with willow. Otherwise, any saplings — fruit trees, conifers, deciduous trees — will work, though you’ll be somewhat limited to straight lines rather than curves.

Use small nails, and for stability nail from both sides. After nailing I first like to wrap wire on each join, then an attractive cord to cover the wire.

The compliments you’ll receive might encourage you to make more than one.

P.S. They make great presents as well.

Kathleen Bander of Bellingham is a life-long gardener. Her column will appear in The Bellingham Herald weekly through the summer growing season. If you have a gardening question you'd like answered in the column, please email it to For more gardening information online, go to