The large apricot in my neighborhood is in full bloom. So is the forsythia. This mean the time is ripe for pre-emergent herbicides, those products that prevent the germination of foxtails, crabgrass and many other weedy grasses that invade our gardens and lawns.

These products will not control cheatgrass (downy brome), flixweed or red stem filaree as these are already in vigorous growth as they germinated last fall. These products also may not control prostrate spurge as it won't germinate until some products are no longer effective.

When applying a pre-emergent herbicide, use one that is separate from lawn fertilizer. The amount of fertilizer you apply to your lawn at this time of year should be half of what is applied when you use fertilizer and pre-emergent combination product. If you use corn gluten as a pre-emergent it may take three years of application before you have effective results.

If you plan on aerating your lawn, do that prior to applying the pre-emergent. The pre-emergent works by creating a chemical barrier through which weeds seedlings cannot emerge. Aerating after applying such a product will poke holes through this barrier allowing weeds to come through and invade your lawn. After aerating your lawn try to apply a fine organic matter that will filter into the open holes. This extends the effectiveness of the aeration and can greatly increase the rooting depth of the grass.

Mesa Ultra, a fine textured product that works very well to fill aeration holes, used to be available from the Mesa County Compost Facility on Orchard Mesa. Last time I checked they did not have any available. You can contact them at 263-9319. Applying the pre-emergent is the last step in this process.

While you are working on your lawn, check out your roses and other shrubs. Some were badly damaged by bad weather last November. The cold air that was trapped under our inversion most of the winter didn't help either. We experienced a drop in temps within just a few days in November which did most of the damage. Hybrid tea and other grafted roses were severely damaged as they don't acclimate as soon for winter as many other plants. Tim, Jane and I pruned a rose garden last Friday in a neighborhood rose garden. Some of the hybrid tea roses had to be cut back to 2 to 4 inches from the graft; some were dead back to the ground.

Austrian pines and Blue Atlas Cedar also suffered and I'm not sure if they will recover. Those that were well-established may recover sometime in the next couple of months. Those that were planted last fall may be a lost cause. Evergreens that lose more than 50 percent of their needles often don't recover. If you have a warranty on such a tree, you might want to take advantage of the option to have the nursery that warranted your tree provide a replacement.

Siberian elms (Ulmus pumila) certainly weren't damaged by the cold. They are setting thousands of seeds to be shed later this spring. This tree is from Siberia and grows well into northern Canada where temperatures are much colder than we experience. The Chinese elms (Ulmus parvifolia) at the Mesa County Arboretum, being native to China, Japan, North Korea and Vietnam, also came through the winter with flying colors. Unlike the Siberian, the Chinese elm produces its seed in the autumn.

Give us a call at 244-1836 if you have any questions about your plants.

Dr. Curtis E. Swift is the area horticulture agent with the CSU Extension. Reach him at Curt.Swift@mesacounty.us. or visit WesternSlopeGardening.org.