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The Homeowners Column
Garden “to do” list
Extension Educator, Horticulture
I've been writing this weekly column for the Champaign-Urbana News Gazette for 14 years now; actually for 14 years and 20 weeks. That comes to 748 columns and 748 frantic flashes of frenzy when I shriek, "What am I going to write about this week?" Out of all the topics I cover, I receive the most comments about my "to do" lists. We all know when we have to pay our taxes, when to expect a birthday card, and when we should have gotten an anniversary card from a forgetful spouse, but when to prune the lilacs remains a mystery. If you have a nagging feeling you should be doing something right now and you're pretty sure the feeling has nothing to do with anniversaries, here is your garden "to do" list.
- Remove spent flowers on spring flowering bulbs, but wait until foliage ripens naturally before removing it.
- Remove spent flowers of peonies, but do not remove leaves until fall.
- Set flower supports early. Let plants grow through them.
- Plant tropical water lilies when water temperature is over 55º F.
- Over-wintered tender annuals or tropicals such as hibiscus, gardenia, mandevilla, and geranium may be pruned, cleaned, and fertilized. Gradually move to protected location outdoors.
- Begin pinching top 1-2 inches of new growth on chrysanthemums to encourage full bushy plants. Stop pinching in early July.
- With clump-forming perennial flowers such as asters, beebalm, and tall phlox pinch out the top growth of the front half of the clump. This technique extends the bloom time since the front half will bloom about 2 weeks later and also shapes the clump into cultured tiers.
- Experiment with pinching back the top growth of tall sedum to keep it from flopping apart. Smaller flowers will arrive later, but will be more numerous. If the plants are getting plenty of sun, this may be a good alternative to staking.
- Severely prune sage, butterfly bush, Russian sage, and Caryopteris to stimulate growth. Remove winter-killed stems on roses.
- Fertilize in early May with one pound of actual nitrogen per 1,000 square feet. Slow release nitrogen forms are preferred.
- Continue post-emergence herbicide treatment for broadleaf weeds if necessary.
- Pick strawberries. Remove any rotten fruit to reduce picnic beetle populations.
- Continue control of insects and diseases on fruit trees.
- Pinch azalea and rhododendron blossoms as they fade.
- Fertilize azaleas after bloom. Use fertilizer for acid-loving plants.
- Prune spring flowering shrubs such as lilac, weigela, viburnum, and flowering almond soon after bloom using renewal method. Prune oldest stems to the ground to encourage better flowering.
- Monitor pines especially Scotch and mugho for caterpillar-like sawfly larvae on new shoots. Hand removal is effective or insecticide sprays of spinosad, neem oil or carbaryl.
- Late May scout for pine needle scale and oystershell scale crawlers by circling stems with inverted black tape. Young crawlers are present about the time bridal wreath spirea is in late bloom or has finished bloom. Timing is crucial for scale control. Insecticidal soaps and summer oil sprays are effective.
- Early June scout for euonymus scale when catalpa starts to bloom.
- Mid-May plant sweet corn, squash, tomatoes, eggplant, sweet potato, and other warm loving crops.
- Thin carrots and beets to allow root development.
- Continue to harvest asparagus and rhubarb.
- Prune sage to stimulate new growth.
- Plant transplants or seeds of annual herbs such as basil and dill. Sow extra dill or parsley for the swallowtail caterpillars.
- Do not irrigate late in afternoon. Foliage should be dry at night to help prevent diseases.
- Practice good sanitation. Remove and destroy diseased leaves.
- Mulch with organic mulches such as wood chips to reduce weeding and conserve moisture.
- Be sure to read, understand, and follow all pesticide label directions.
- Send me ideas for my column.