Wichita gardener’s almanac (March 20)

Spring temps — It’s officially spring, and it feels like it this weekend. The forecast shows no temperatures below freezing at this point. However, as we know from sad experience, the weather can change on a dime and plunge us back into winter. The average date of the last spring freeze in Wichita is March 29, and the average last frost is April 11. That means half the time it’s later.

Some vegetables can take frost if hardened off first; cabbage, broccoli, cauliflower and onions can take temps as low as 20 if they’ve gradually been introduced to sunshine and colder weather, Ward Upham of K-State says in the Horticulture 2015 newsletter. Some annuals, such as pansies and snapdragons, can take a light frost and be planted now, extension agent Bob Neier says. Otherwise, keep an eye on the forecast and wait a bit before introducing plants that need it warmer.

Remove dead pine trees — Pine trees that have died of pine wilt should be removed by April 1 to help prevent the spread of the insect-carrying disease. New pine-wilt infections usually are evident from August to December, and the entire tree dies within several weeks or a few months, Megan Kennelly of K-State says. All of the wood must be destroyed by May 1, which is when infected beetles start to come out of dead trees and head for new hosts. Cut the tree to the ground – don’t leave a stump. Chip or burn the wood immediately to destroy the beetles and nematodes; do not keep pine wood around for firewood, Kennelly says.

Green weeds — Clumps of wild onion and wild garlic provide some bright green in the early-spring landscape that is not necessarily welcome. If you want to eradicate the weeds you can use 2,4-D or 2,4-D plus MCPP plus Dicamba (i.e., Trimec, Weed-Out, Weed-B-Gon) on a March day that is at least 50 degrees. Weed Free Zone and Speed Zone contain Trimec plus carfentrazone and give a quicker response at lower temperatures near 50 degrees, Upham says. Add a spreader-sticker to the spray if it’s not already present for more effectiveness, he says. These products also can be used on dandelions.

Speed Zone and Weed Free Zone can be tried on star of Bethlehem though they may not be as effective on this weed; a commercial company can use Quicksilver on them, Upham says.

Plant — When the soil is dry enough to be crumbly: cabbage, broccoli, cauliflower, lettuce, potatoes, radishes, onions, peas, spinach, strawberries, rhubarb, turnips, beets.

In the asparagus patch — Remove last year’s growth from asparagus plants and fertilize before spears emerge, Upham says. Use a 10-20-10 fertilizer, or fertilize according to the results of a soil test. Lightly rake or till in. Weeds also can be controlled now. Lightly till or hoe between crowns, mixing in some organic matter at the same time if you like, Upham says. Herbicides can be used before asparagus emerges; glyphosate (Roundup, Killzall) will kill weeds that are already growing, and the pre-emergent trifluralin (Miracle-Gro Weed Preventer Granules and Monterey Vegetable and Ornamental Weeder) will kill weed seeds as they germinate. Pull broadleaf weeds.

Garden events

Fully staged orchid show this weekend — Orchids will be landscaped into exhibits this weekend at Botanica as the Kansas Orchid Society sponsors a fully staged “Spring Into Orchids” show. Exhibitors from New Mexico, Oklahoma and Nebraska as well as Kansas growers will take part in the American Orchid Society-judged show. Vendors will have orchids and growing supplies for sale, and orchid society members will be on hand to offer growing advice. The show is from 10 a.m. to 5 p.m. Saturday and 10 a.m. to 4 p.m. Sunday. Admission to the show is free.

Talk on new annuals — Dan Parcel of Kaw Valley Greenhouse will be at Botanica on Wednesday to talk about new annuals for 2015 and how Kaw Valley tests new annuals and perennials to find the ones that grow the best here. The lecture, at 12:15, is included in Botanica admission. Lunch by Blue Moon Caterers will be available for $8 from 11 a.m. to 12:15 p.m.

Spring Card and Game Party — Project Beauty will have its annual Spring Card and Game Party at 12:30 p.m. Thursday at Botanica. Refreshments will be served, and there will be door prizes. Bring your bridge group, favorite card game or any other game to play. Tickets are $7 in advance, $8 at the door. Call Nancy Boewe at 316-681-0000 for advance tickets.

Harvey County Home & Garden Show — Several garden talks by K-State and other experts will be part of Harvey County’s Home & Garden Show next weekend in Newton. Plant suppliers, home and garden exhibitors, an art show and a farmers market also will be part of the event. Hours will be from 8:30 a.m. to 5 p.m. March 28 and noon to 5 p.m. March 29 at the National Guard Armory at 400 Grandview. Admission is $1. Kids can make a gourd birdhouse at 2 p.m. both days, and experts will answer questions from 10 a.m. to noon March 28.

Here is the schedule of seminars:

▪ March 28: 9 a.m., water-wise plants by extension agent Bob Neier; 10 a.m., small trees with big ambitions by Jason Griffin of the John C. Pair Horticulture Center; 11 a.m., landscaping the home entry by Scott Davies of Brady Nursery; 1 p.m., no-fail shrubs plus fun new ones to try by Cheryl Boyer of K-State; 2 p.m., the science of plant establishment in the landscape by Boyer; 3 p.m., how to attract monarchs by Scott Vogt of Dyck Arboretum of the Plains; 4 p.m., how not to waste water by Pater Daniels of Wichita Rain Barrels.

▪ March 29: 1 p.m., bees and pollinators in your garden by Debbie McSweeney, 2 p.m., from trash to garden treasure by master gardener Brenda Mays; 3 p.m., savory plants for your garden by Kay Neff of Neff Family Farm; 4 p.m., getting control of varmints in the landscape by veterinarian and master gardener Cyril Brown.

Native-plant enthusiasts — The Kansas Native Plant Society will meet from 3 to 4:30 p.m. March 28 at Braum’s Party Room, 2121 N. Ridge Road. Any native-plant enthusiast can join the group in discussing how to prepare flower beds, where to see natives in local commercial landscapes and in learning about the aster plant family. The meeting is free but please RSVP by calling 316-258-6341 or e-mailing KSKLD@yahoo.com.

Tulips, Fairies & Forts — Botanica will usher in the spring season with special activities the four Saturdays from March 28 to April 18. Tulips, Fairies & Forts will be from 10 a.m. to 2 p.m. each of the Saturdays and will be included in Botanica admission or membership. Each Saturday will feature a fairy-house competition ($5 entry fee, entries due April 11), crafts, fairy dress-up and props, games, a scavenger hunt, fort-building, bubbles, forts throughout the gardens, fairy story time, and a bounce house. Then each Saturday will have its own features:

▪ March 28: Poppy the Clown from 11 a.m. to 1 p.m.

▪ April 4: The Bug Lady and a face painter from 10 a.m. to 1 p.m.

▪ April 11: Tanganyika Wildlife Park from 10 a.m. to 2 p.m.

▪ April 18: Specialty art project with Paint the Towne from 10 a.m. to 2 p.m., Poppy the Clown and balloon artist from 11 a.m. to 1 p.m. A fairy tea party also will take place that day; the cost is $30, and reservations are required. See details at botanica.org or call 316-264-0448.

Annie Calovich

This story was originally published March 19, 2015 at 5:37 PM with the headline "Wichita gardener’s almanac (March 20)."