Garden Coach 7/9/2020

1. This is the fourth week in a row that we have started our discussion with – "since it will be hot (again this week); water, water, water" all of the landscape plants (vegetables, flowers, roses, trees and shrubs).
2. As uncomfortable as it is for us humans, the high humidity has been a saving grace for our gardens.
3. With less wind, the plants are not “transpiring” as much so there is not as much drought stress as there could be.
4. Watering plants at least once a day when the temperatures are over 85 should be sufficient. 
5. If you rely on a sprinkler system, be sure to use rain gauges (or even empty tuna fish cans) to measure how much water is being delivered to plant root zones.
6. Make sure that you are watering the soil, not the leaves of the plants. Get the water to the roots. 

2. Things to watch out for in your gardens: (All of these have shown up at the Plant Information Center windows, since we last talked):
3. As it gets hotter and hotter, I am seeing samples of Anthracnose on every plant that can get it – especially Boston Ivy, and Maples, Oaks, Gingkos and more. One benefit of the extreme heat is that all the sporulation has stopped because the fruiting structures have been "roasted". There is very little risk of secondary re-infection.
4. ALL of the fungal leaf spot diseases are showing up now – More and more “rusts” on apples, crabapples, hawthorns and roses are showing up. Unfortunately, once the spots show up there is nothing to do except keeping the plants out of stress by watering and fertilizing.
5. Slugs are creating a lot of leaf damage on Hosta.
6. TERRIBLE NEWS FLASH - This week I saw the adult Viburnum leaf beetles –this means that you need to use a spray form of insecticide to kill them more quickly and prevent egg laying on the young stem tips. If you  used the systemic insecticide soil drench at the “root collar” – where the trunk goes into the ground, the plants are protected. (BioAdvanced or Bonide Systemic Insecticide 12 month soil drench.)  When the adults feed on the leaves they will ingest the insecticide and get killed, stopping the damage. 
7. Continuing in the vegetable garden is the “Cabbage Looper”, a pale green caterpillar on the undersides of the leaves that makes huge holes!  Use a contact Earth Friendly natural insecticide to control them. Spray one day and harvest 24 hours later. Bonide Tomato and Vegetable Insect Spray.
8. Slugs are active and are leaving holes in Hosta leaves. Use Sluggo at the rate of 1 teaspoon per square feet every 2 weeks for 3 applications. 
9. Lots of Japanese beetles are in many of the gardens - use a systemic insecticide late in the afternoon or early evening.

3. What to do in the garden: 
4. It is time for the July application of the soil drench for roses, crabapples, grapes and other members of the Rose family with preventative All-In-One Rose & Flower Care
5. Treat Boxwood and Viburnum shrubs and Magnolia trees with systemic insecticides to prevent Boxwood leaf miner and Viburnum leaf beetle.
6. Keep removing weeds from the perennial garden beds, vegetable garden beds by hand pulling. Never let them flower and produce seeds or the saying goes, “you will be pulling them for the next 7 years!".
7. ALWAYS water plants first before spraying with anything or fertilizing.

4. What not to do in the garden in this heat:
5. Do not use herbicide to kill weeds in the lawn - all products warn to not use when temperatures can go over 85 in the next 30 days. Realize that the window of opportunity is passed and wait until August 15 through September 15.