Gardening ABCs for June
from the Johnson County Master Gardener Association
Avoid fertilizing St. Augustine grass after mid-June. Gray leafspot season won’t be over until September and high-nitrogen plant foods accelerate the development of this fungal disease. But continue to fertilize Bermuda every two weeks through early October.
Avoid any severe pruning during this time of the year.
Apply an iron chelate or iron sulfate mixed with organic materials to plants suffering from iron deficiency, which causes the leaves to turn yellow while leaving the veins dark green. (No, not Geritol! That’s for a different kind of iron deficiency!) Iron deficiency is common in alkaline soils and frequent applications of Ironate or green sand during the growth season may help control the condition.
Begin pruning roses as soon as the bloom cycle is over and deadhead salvias, irises and daylilies after the flower stalks have dried completely. Remove the tops off of chrysanthemums (several inches) to encourage compact growth.
Begin removing webworms from pecan and walnut trees while the webs are still small and spray evergreens, especially junipers with B.t. biological worm spray, to control bagworms.
Beware of using insecticides in your garden or landscape if you’re trying to attract butterflies and/or ladybugs. Try to control pests manually by picking them off or cautiously spraying each plant individually in order not to contaminate butterfly-reserved or lady bug-inhabited plants.
Control vigorous perennial weeds like dock or dallisgrass by spot removal while the plants are still young.
Control early blight in tomatoes, which causes the lower leaves to turn yellow, by removing the lower leaves or using a recommended fungicide, 2 to 3 times in 10-day intervals.
Complete pruning of blackberry canes that have borne fruit. These canes will never bear again, so remove them all the way to the ground. Then trim off the last couple of inches on the new canes in order to encourage side branching for next year’s fruit.
Complete the raising of your mower blade as turf grass growth slows down. Your maximum recommended setting will be attained sometime during June and should be left there throughout the growing season.