Spring is here. That time of renewal and joy as we wander our gardens and take stock of what works and what needs a “tune-up.”

April Ideas

ONE – Check all of the sprinklers and drip lines to be sure they are working properly and not wasting water. There is a comprehensive spring tune-up guide for sprinklers in the 2010 April - June Master Gardener Newsletter which can be found at https://vms.ucanr.edu/mg/files/documents/6272Garden%5FNotes%5F2010%5FCommunity%5FNewsletter27622.pdf

TWO – This is a great time of year to plant citrus trees if there is a vacant, sunny spot in the landscape. Make a hole about twice the width of the root ball. Build a cone of soil in the center of the hole tall enough so the new plant will be level with the surrounding soil when placed on top of it. Gently knock the plant from its pot. Use fingers to gently uncoil and separate any bunched-up roots. If the root-ball is solid, use a knife to score four ½-inch deep cuts around the sides and one on the bottom. Set the roots atop the cone, refill the hole and water thoroughly to eliminate air pockets. The beginning of the root flare on trees should be visible at or above the surrounding soil. Add a 2- to 3-inch layer of mulch around the plant, keeping the mulch about an inch away from the trunk.

THREE – Now is the time to fertilize lawns and many garden plants. Cane berries, citrus, fruit trees, palms, and heavily flowering shrubs will flourish with slow-release fertilizer products. Maintaining good fertilization can keep your plants vigorous and help prevent pest problems. Lawns will thrive with an application of fertilizer now. Use a balanced slow release or organic fertilizer according to the directions on the package. Organic fertilizers react more slowly but will eventually provide a lush result. If crabgrass has been a problem in past years, consider a pre-emergent/fertilizer mix. Help preserve our waterways by avoiding getting granules on hardscape surfaces.

FOUR – April is the time to think about control of the “A” pests: Ants, Aphids, and Abiotic disorders. Manage ants in the landscape and around the foundation of buildings with insecticide baits and trunk barriers such as “Sticky Foot.” Sticky Foot can also reduce damage caused by insects that ants help protect such as mealy bugs, certain aphids, and some scale. When applying Sticky Foot to a tree trunk, it is best applied to gauze wrapped lightly around the trunk so that it is easily removed once it is no longer needed. Aphids can be controlled with a strong water spray from your hose. Difficult infestations may need an insecticidal oil or soap to reduce the damage aphids can cause. The best solution would be to look for and avoid harm to aphids' natural enemies such as lacewings, lady beetles and syrphids. Prevent or manage the damage that occurs from aeration deficits, frost, hail, herbicides, wind, and too much or too little water which all weaken plants and contribute to abiotic disorders.

In May

ONE – Prune a couple of things this month. Winter-flowering shrubs (e.g., camellias) need to be pruned prior to the formation of next year's flower buds. Pruning pine terminals to direct growth in young plants and retard growth in more mature plants should only be done during candling (new shoot growth) during late spring to early summer, so May is usually an opportune time.

TWO – It's May – think mosquitos and mulch. Mosquitos are nobody's friend. To reduce the spread of this pest and the diseases it can bring, eliminate standing water in gutters, drainpipes, flowerpots, old tires, etc. Place Bacillus thuringiensis subspecies israelensis (BT, commonly referred to as “mosquito dunks”) in birdbaths and ponds to selectively kill mosquito larvae. Apply mulch to areas of the garden and under trees where existing mulch is thin or soil is bare.

THREE – Fill out vegetable gardens with transplants of tomatoes and peppers. Around the middle of May is a great time to plant seeds of pumpkins, beans, corn, squash, cucumbers, and melons. For interesting and unusual fall decorations, consider growing pumpkins or winter squash that are not the ordinary jack-o-lantern choice. Beef up a flower garden with a little height. Shorter bedding plants get the front row spot followed by tall, upright bedding plants and finished with some summer-blooming vines grown on a sturdy structure that is set in the garden at the same time planting occurs. It is difficult to add the structure once the plant needs it. As the vine grow, train the shoots to the support with self-gripping Velcro, plant tape, or twist ties. Start with flowers in six packs. Planted in May, these little gems will explode with summer color in a few weeks. If instant color is needed, think about 4-inch pots instead.

FOUR – Aerate lawns this month. Lawns that get a lot of heavy fool traffic develop compacted soil which makes it difficult for water, fertilizer, and oxygen to reach the roots. If a screwdriver can't be pushed up to its handle into the turf, it's time to aerate. Use an aerator that either produces a core or a water wash to dig holes. Spike aerators just add to compaction. If using a machine aerator, be sure to mark and avoid all sprinkler heads. Some machine aerators require a lawn to be moist, but not soggy. Irrigate a day or two before aeration if soil is dry.

June Notes

ONE – Bees are essential pollinators. A variety of flower shapes and colors will attract bees to a garden. Look for flowers and plants that are native to this area for growing ease, adaptation to the local climate, and to serve as an attractant to honeybees. Planted near or among a vegetable garden, flowers attract bees for pollination and a bountiful harvest.

TWO – Basil and cilantro planted now will produce fresh herbs all summer. Both annuals do well in pots and love sun and ample water (easy to control if the herbs are in pots). Start basil from seedlings, but sow cilantro seeds directly in the pot – they germinate quickly. Begin harvesting when plants reach 6 inches tall. Other crops to plant from seed in June are cucumbers, green beans, melons, parsnips, pumpkins, and squash.

THREE – Clean up mummies and old fruit and nuts in and under trees to avoid harboring pests and deter borers by deep watering trees. Paint the trunk and scaffolds of young trees with white interior latex paint diluted with an equal amount of water to protect from sunburn.

FOUR – Still have a lawn and wonder just how much water it needs during the hot summer months in the valley? Lawns need about two inches of water per week during the summer heat. To determine lawn sprinklers' output, place several flat-bottomed containers (such as tuna fish cans) around the lawn, turn on the sprinklers for a half hour and then measure the water in the containers. Adjust the sprinkler coverage if needed and reset the amount of time they water according to the results of the timed test. Water lawns and the rest of the landscape early in the day to reduce water wasted due to evaporation and be cognizant of appropriate days to water if applicable. Better yet, start thinking about how to minimize or eliminate the lawn in your landscape to save water during these drought years.

Deep-water established plants often enough to prevent wilt and promote deep rooting as temperatures start to rise. Check the soil moisture around roots with a moisture meter probe or by digging down with a trowel. Soaker hoses apply water directly to the soil with minimal evaporation.

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Information for this article was gathered from:

www.ipm.ucdavis.edu
www.sunset.com/garden
www.farmerfred.com
A Valley Gardener's Journal by San Joaquin Master Gardeners
CA Month by Month Gardening by Claire Splan