May Gardening Tips
What to Plant
- May is a great month for planting new trees & shrubs. Use Worm Gold Plus when planting. Use DeWitt® 12-year Weed Barrier Landscape Fabric to prevent weeds from coming up in your garden beds.
- Plant irises, canned roses, tropicals and tuberoses
- Continue to plant dahlias, begonias–and get in the gladiolus bulbs. Add some Down to Earth Bone Meal to the planting hole for great root development and beautiful blooms!
- Prepare to plant a giant pumpkin in early June for Halloween.
- Transplant potted bulbs into the ground.
- Plant zinnias, morning glories and other heat loving flowers. Replace cool-season bedding flowers with summer-season flowers.
- Plant warm-season lawns such as Bermuda or Paspalum.
- Plant vegetables and herbs – It’s time to plant warm-season crops like tomatoes, squash, peppers, sweet potatoes, cucumbers, melons, okra and corn. Also plant basil, mint, oregano, parsley, rosemary and thyme and other heat-lovers. Consider using Superthrive® for healthier, fast growing plants. Superthrive® is excellent for reducing transplant shock and reviving stressed plants. You can also plant a pumpkin this month or wait until June.
- Plant seeds or seedlings for corn, green beans, melons, squash, cucumbers, okra, sweet potatoes and other heat-lovers. We carry a large selection of Quality STOVER® seeds or Vegetable, Herb and Flower Packs.
- Continue to purchase, plant, and transplant succulents.
- Purchase epiphyllums.
- Plant petunias. Pinch them back when you plant them.
Harvest your summer vegetables as soon as they are ready. Don’t let them rot and drop to the ground. This can bring insects and disease. See our harvest guide.
Feeding and Maintenance
- Fertilize both cool season (fescue) and warm season (Bermuda & St. Augustine) lawns using Best® – Turf Supreme 16-6-8 (a fast acting fertilizer with iron for a deep green which lasts up to 8 weeks) or Best® Super Turf 25-5-5 (a slow release fertilizer which lasts for up to 12 weeks for a longer green and less mowing! ). For those Organic Gardeners use G&B Organics Natural Lawn Fertilizer Is an excellent organic option to keep your lawn healthy. For convenience in small areas use a Hand-Held spreader. For larger areas use a Broadcast Spreader.
- Mow cool season lawns long and warm season lawns short.
Plants, Trees and Shrubs
- BENEFICIAL INSECTS – Beneficial insects such as the almost microscopic parasitic wasps, praymantis, ladybugs, etc. keep other insect pests away from your vegetable gardens by eating aphids, scale, and other annoying intruders. You can use beautiful flowers to tempt these garden friends into your garden. Try putting some of these flowers near to your rose garden for aphid control!
- VEGETABLES – Keep planting warm season crops. Stop watering onions and garlic grown for bulbs when leaves being to turn yellow. Dig bulbs when tops have fallen over and place in a shady, well ventilated area to cure. Fertilizer warm season crops to promote growth. Try Dr. Earth® Tomato and Vegetable Food. Fertilize peppers when flowers first show. Check for pests. Use a pest control product made for use on vegetables. Continue to tie up and sucker tomatoes.
- HERBS – Pull out spend winter annuals such calendula. Prune back perennial herbs like rosemary. Continue to harvest Yerba mansa, mint, elderberry flowers and lavender blossoms.
- FRUIT TREES & VINES – Continue to feed avocado and citrus trees. Use a good all around fertilizer such as Dr. Earth® Fruit Tree Fertilizer or contact us to learn of other conventional and organic fertilizers that will fit your growing needs best! Check citrus for pests and diseases. Irrigate as needed to maintain adequate soil moisture. Apply enough water to wet the soil at least two feet deep. Only apply water about 3 inches deep in loam soil. Watch for chlorosis on your citrus. This yellowing of the leaves between the veins is a sign of iron deficiency for the plant. Feed with a good iron supplement such as Ironite® Mineral Supplement.Wash fruit trees periodically with a forceful spray of water to remove dust, honeydew and pests like aphids, whiteflies and spider mites. Control ants. Use Tanglefoot® or AntPro® Liquid Bait and Bait Stations.
- DECIDUOUS FRUIT – Continue to thin out fruit on apples, pears and stone fruits when they are about one-half inch in size. Space fruit four to six inches apart. Leave one fruit per spur.
- ROSES – Deadhead stems and canes when blooms are spent. Deadheading fading flower blossoms will keep your garden neater and flowering better & longer. Water well as heat increases. Roses need one inch of water twice a week during the warm season. Potted roses need even more. Spray wash the bushes with water daily in the early morning to control powdery mildew or spray with a fungicide according the label directions. Watch for Blossom rot; a fungus that shows up as red spots on white and yellow petals and brown spots on petals of other colors. Remove affected blooms.Feed roses based on the recommended schedule for your chosen fertilizer. Some good options are G&B Organics Rose & Flower Food, Gro Power® Flower N’ Bloom or Bayer® Advanced combination control Rose Foods.
- BEGONIAS – Check tuberous begonias to repot or add fresh soil. Stake if needed. Wash insects off with water. Pinch back once or twice and fertilize for more blooms and bushier canes.
- FUCHSIAS – Continue to water regularly. Use a liquid fertilizer when watering during their growth period (April through September). Stop pinching back fuchsias. Remove berries (seed pods) from fuchsias after flowers fall.
- CAMELLIAS – Feed your camellias as part of your annual fertilizer program. A good schedule of feeding is three times a year. March should have been your first feeding. Feed again in May and again in July. The rule of thumb is to feed camellias six to eight weeks after the last blooms fall. Feed again six to eight weeks later, then one more feeding six to eight weeks after the last. Continue using the fertilizer of your choice. Suggestions are a pre-made mix such as G&B Organics or Lilly Miller® Camellia and Azalea Food. They like acid food. Watch for aphids and hose them off with a spray of water. Keep well watered, but not soggy. Prune unwanted new growth.
- TROPICALS – Continue with a fertilizer schedule for your tropical plants. Tropicals do best when feed during the growing season (spring through fall). This will depend on your schedule and type of fertilizer used. We suggest with Gro-Power® Premium Palm & Tropical Plant Food 9-3-9 or Apex® 13-5-8 Palm Plus. Remove only dead and dying foliage from date palms
- CACTUS & SUCCULENTS – Feed all container-grown succulents with a well-diluted complete water soluble fertilizer such as Growmore All Purpose. Make sure drainage is good in all container plants. Now is the for winter/spring growers such as aeoniums, dudleys and senecios. Take cuttings for propagation.
- DAHLIAS – Feed dahlias with a balanced nitrogen fertilizer. Spray as necessary to control insects. Watch for leaf miners, thrips and aphids. Try using a systemic. If spraying, use a weak solution on new foliage. Water when top of soil is dry. Soak deeply and often when buds are forming. Pinch out center of plants when two or three sets of leaves have developed. Plant tubers now when soil is warm. Tubers should be planted four to six inches down and planted with “eye” up. Stake at this time. Keep moist but not too wet. Protect from harsh sun. Protect from snails and slugs.
- PELARGONIUMS – Avoid pruning or cutting. Remove dead or damaged leaves to prevent molds and fungus. Watch for geranium rust. Use Immunox® to treat. Immunox® is a non-sulfur based product. Keep the soil moist and the foliage dry. Fertilize with an all purpose plant food every 2-3 weeks. Protect against whitefly, budworm & aphids. Use a product that contains both an insecticide and fungicide.
- ORCHIDS – Protect plants from sun damage as temperatures start to rise. Finish repotting. Be sure to soak first this late in the season. Water more as plants increase their growth rate. Bring some indoor plants outside for the summer. Watch and protect from insect infestations. Divide and repot cymbidiums that have outgrown their containers. Cut off bloom spikes from cymbidiums after flowers fade.
- EPIPHYLLUMS – Prune plants to shape. Plant cuttings after they flower. Bait for snails & slugs. Use horticultural oil for scale. Keep soil damp. Protect from hot summer sun.
- IRIS – Prepare beds for planting. Work in humus, soil sulfur & decomposed manure. Allow cut surfaces of rhizomes to dry and be exposed to sunlight before planting or give a light dusting of soil sulfur.
- BROMELIADS – Water throughout the summer by spraying. Bromeliads absorb moisture and nutrients through their leaves. They do not like soggy roots so don’t over-water. Be sure to protect from sun. Use shade-cloth for protection if needed.
- PLUMERIA – Potted plumeria should be moved from protected areas to full sun. Continue fertilizing with a low nitrogen fertilizer such as Gro Power® Flower N’ Bloome 3-12-12. Plant new or repot plants to replace old soil with a fresh mix. Use one-half cactus mix such as Kellogg® Palm & Cactus Mix and one-fourth perlite and one-fourth Worm Gold Plus®. Keep soil at the same level as before.
- FERNS – Divide and mount staghorn ferns. Remove old dead fronds. Keep humidity up. Most ferns are starting full growth now. Water frequently and fertilize with half-strength, slow release fertilizer such as G&B Organics Palm & Tropical.
- IRON DEFICIENCY? – Many have asked us what is causing yellowing in the leaves of their citrus, camellias, and gardenias. Iron deficiency. Do the leaves near the top of the plant have green veins but yellow in between the veins? Time for either a foliar spray or a soil drench such as Grow More® Iron Chelate or Ironite® Mineral Supplement. This will help return those leaves to green!
- TREES & SHRUBS – Continue your fertilizer routine. There are many products available in both organic and conventional style feeding. Continue to prune your ornamental shrubs for hedges.
- PRUNE – Prune winter and spring-flowering vines, shrubs, trees and ground covers after they finish blooming.
- NATIVE PLANTS – Most native plants can go three to four weeks between watering, but Riparian natives need to be watered once or twice a week. Wash the dust off shrubs and trees once a month. Harvest wildflower seeds. Pull out wildflowers after they dry. Keep planting at a minimum until fall. If you do plant, make sure to water 3 – 5 times for most new plantings. Then they can generally make it with little water through summer. Visit Las Pilitas Nursery for best times to plant.
- ATTRACT BIRDS – Attract a variety of birds to your yard with Kaytee Bird Seed and bird feeders. Place some hummingbird feeders around your yard to keep them coming back. Then relax and listen to the birds.
- MULCH, MULCH, MULCH – If you haven’t already, apply a layer of mulch on flower beds and around trees and shrubs 2-3 inches around the base of plants. It reduces weeds, conserves moisture, and prevents disease. Great stuff!
- Reset your irrigation timer to water more frequently as the weather starts to warm up. Adjust as needed if we get adequate rain fall.
- Water gardens – Check irrigation systems. Fix clogs and broken sprinklers. Adjust spray heads. Begin watering as weather warms. Apply a fresh layer of organic mulch to conserve moisture.
- Apply at least one inch of water twice per week to keep roses well hydrated.
- Taper off watering those California native plants that do not accept summer water. Most native plants can go three to four weeks between watering, but Riparian natives need to be watered once or twice a week. Also make sure to water 3 – 5 times for most new plantings. Then they can generally make it with little water through summer.
- As the weather becomes drier, keep up with watering. Even highly drought-tolerant plants need irrigation. Water large cacti, for example, once a month and agave and yuccas every three weeks. Be sure to water most garden plants regularly. Try using a Dramm Water Wand for easy watering. Pair it with a Gilmour® Flexogen Hose for maximum kink resistance.
- Water lawns – Check irrigation systems. Fix clogs and broken sprinklers. Adjust spray heads. Begin watering if weather warms but only after soil has partially dried. Check with your local water department or cooperative extension service for lawn watering guidelines.
- Now is a perfect time to start planning on how you are going to save water in your landscape, if you haven’t already. Installing or retrofitting an existing irrigation system to utilize the most up-to-date technology will help you save water. Grangetto’s can help you make the SMART WATER CHOICE in your landscape. Call us or stop by your favorite location so we can help! Here are some water saving devices
Pests to Watch out For
- Control indoor & outdoor pests – To control insects like spiders, fleas and ants, use Spectracide® Triazicide Once & Done, which provides up to 12 months of insect protection. It controls insects in lawns & around homes so they don’t come inside!
- Animals – Warmer weather brings out animals such as skunks, raccoons and opossums. Trap them with Havahart Traps. We carry a large supply and they are very effective.
- Squirrels – Use Havahart Traps, Protecta Bait Stations, Wilco Squirrel Bait and Station or Squirrelinator Multi-Trap.
- Control mosquitoes – Use Mosquito Dunks in ponds or standing water to help control mosquitoes.
- Rabbits – protect your vegetables and herbs from foraging rabbits! Use Rabbit Scram Repellent to keep rabbits away. This repellent is natural and organic and works as a barrier so it never has to touch your plants.
- Snails & Slugs – Use Organic Sluggo® Plus, Original Sluggo® or Corry’s® Snail & Slug Meal or Pellets.
- Aphids – Control aphids with insecticidal soap and beneficial insects. Safer® Insect Killing soap is a good organic choice.
- Thrips – Wash foliage with water from a garden hose. For stronger infestations use Bayer® Advanced Tree and shrub Insect Control. This is a systemic that gives 12 months of control.
- Coddling moth larvae – Spray walnuts with Sevin when nuts are about the size of a nickel and again three weeks later to control coddling moth larvae.
- Scale – Use Monterey Horticultural oil to control crawlers.
- Lawn pests – Use Bayer® Multi-Insect Killer or Spectracide® Triazicide
- Vegetable Pests – Use Monterey Spinosad for control
- Juniper moths – Spray junipers and Italian cypress for juniper moths.
- Rats & Mice – Use Just Tomcat Rodent Bait.
- Gophers – Use Wilco® Gopher bait to rid your yard of gophers. Also Macabee traps
- Caterpillars – Use Safer® Caterpillar Killer, Monterey® Garden Insect Spray Spinosad. Look these pests on your broccoli and cabbage!
- Rose Pests – Use Bayer® All-in-One Rose & Flower Care, Bayer® 3-in-1 Insect Disease and Mite Control or Neem Oil
- Powdery Mildew – Especially near the coast, this is the time we begin to see powdery mildew on our rose foliage (and other plants too). There are several different foliar fungicidal sprays to that can help. Consider Bayer® Insect Disease and Mite Control for conventional use . Use Monterey Neem Oil or Serenade for organic growing.
- Powdery Mildew on Grapes – Apply a sulfur spray such as Safer® Garden Fungicide.
- Fruit Tree Pests – Use Monterey® Garden Insect Spray to combat caterpillars and other listed pests on fruit trees, vegetables and ornamentals. It is OMRI listed for Organic Use too. For synthetic control use Bayer® Fruit, Citrus and Vegetable Insect Control.
- Lawn Weeds – To control weeds in lawns while giving them a good feeding use Hi-Yield Weed & Feed.
- Weeds – Use Bonide® Crabgrass Preventer or Bayer® Season Long Weed Control in lawns. Use Green Light® Amaze in ornamentals & flower beds. For non-selective areas, use Suppress Organic Herbicide. Be sure to use a good sprayer such as Hudson® Sprayers. DeWitt® Weed Barrier Landscape Fabric prevents weeds without chemicals. It still allows air, water and nutrients to go through. Lay this fabric down before planting your gardens.
Note: All information provided is based on typical season, weather and environmental statistics. These tips are provided for information purposes only and to be used as a general guide. Products/Brands mentioned may be discontinued at anytime and not guaranteed in-stock. Grangetto’s invites you to contact us or visit one of our locations for more specific care instructions.