Q: I’ve had success growing my first pumpkins this year, but I’m trying to figure out when to harvest them.

A: Harvest pumpkins and their winter squash relatives when the rind hardens; you won’t be able to easily dent it with a fingernail. Most pumpkins require more than 100 days to ripen once the flower has been pollinated.

If full ripeness doesn’t happen until sometime in October, that’s okay — the fruits can tolerate a light frost (though the foliage will wither), and harvesting is usually finished by the time we experience heavy frosts or freezes. Pumpkin harvest season tends to peak from late September into October, though depending on your location in Maryland, it could range from mid-September to even early November, according to the state agriculture department.

Cut pumpkins ready for harvesting from the vine, leaving a 4- to 5-inch stem stub as a handle. Be gentle with them so you don’t break the fruit’s skin, which can invite rot. Store harvested pumpkins in a cool, dry location until ready to use for decor, cooking or carving.

To help early-ripened pumpkins resist rot until Halloween, you can discourage microbial growth on the rind by rinsing it with a bleach solution. (One tablespoon of bleach mixed into 16 ounces of water.) Rinse off the bleach with plain water, then dry the rind and store the fruit in an area with good air circulation.

Q: Lots of late-season flowering native perennials are yellow … not a favorite color of mine. Aside from asters, is there a native plant I can add to my pollinator garden in autumn with another color?

A: I happen to enjoy yellow, but I too can get a bit weary of so many late-blooming perennials being golden in color. Asters are a great starting point, and a relative of theirs can add to that cooler color palette: I recommend trying ironweed (genus Vernonia). Two species grow wild in Maryland, among the dozen-plus species native east of the Rockies. The most widespread species in Maryland, and much of the Eastern U.S., is New York ironweed (V. noveboracensis).

Both of our local species have intense violet- to fuchsia-purple blooms in late summer or early autumn. On average, flowering peaks in Maryland from mid-August through mid-September.

The catch in adding a New York ironweed to the garden is that it grows very tall, reaching around 5 to 7 feet high by the time it flowers. This makes it a great companion for other tall-maturing perennials like cup/compass plant (Silphium), Joe-Pye weed (Eupatorium), various perennial sunflowers (Helianthus), and wingstem (Verbesina alternifolia). If you really want to go all-out, an even taller relative is the aptly-named giant ironweed (Vernonia gigantea), which I’ve seen reach 8 to 10 feet. Planted near an elevated deck, it would be a great viewing height for the pollinators it attracts.

There are shorter-growing cultivars and species native to the Eastern U.S. that are alternatives easier to fit into most gardens. Examples include narrowleaf ironweed (V. lettermanii) and its hybrids. Some have improved resistance to the one or two leaf diseases that New York ironweed can contract, though it’s not a given that an infection would decimate the local natives.

University of Maryland Extension’s Home and Garden Information Center offers free gardening and pest information at extension.umd.edu/hgic. Click “Ask Extension” to send questions and photos.