Gardening Tips for May 2026

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• Summer Annuals - Zinnias Profusion Series, Petunias, Salpiglossis sinuata, Celosia, Lobelia .
• Perennials - Leonotis leonurus, Lobelia cardinalis (likes water but worth it), Centaurea, Mimulus, Nemesia.
• Shrubs - Rhododendron, Roses, Abutilon, Lantanas, Phlomis fruticosa.
• Vines- Clematis hybrids (may re-bloom when deadheaded), Mandevilla and Thunbergia alata (frost sensitive-used as annual).
• Veggies- Zucchini, Tomatoes, Lettuce, Basil, Scarlet Runner Beans.
• Extras- Metal Loop Stakes, Insecticidal Soap, Water Holding Polymers, Maxsea Fertilizers.
• Shopping Tip - Ask your local nursery which days they get the biggest delivery so you can time your shopping for best selection.
   

Tips for Growing Vegetables.

• Planting - Prepare flower beds before going shopping for plants. You'll be so happy when you can come home and can install your plants right away. The plants will be happy too! We've all left plants out that died in the heat. Add compost to the soil and apply a 3 inch layer of compost on top as mulch after planting. Mulching keeps soil moist longer. Watch The Gardening Tutor video: Mulch vs. Compost. 
•  Summer Annuals - Do you like Nasturtiums? Now is the time to plant your seeds or seedlings of Tropaeolum (Nasturtium). Remember that once you have established your plants you can start to hold back on the water. Watering Tropaeolums less creates more flowers. Watering more creates bigger leaves and fewer flowers. Sunflower seeds can be sown every few weeks now for a succession of blooms all summer. These are also great starter seeds for kids since they germinate quite quickly. Zucchini and Cucumbers seeds germinate quickly too!
• Watering - We ask a lot of our plants. Here in our Mediterranean climate (Zone 9) we don't get the summer rains other areas do. Here we have approximately a six month period for possible rainy days followed by a six month period of drought. With this in mind, now is the time of year it’s super important to open the end of each mainline and run that zone for a few seconds to flush drip irrigation lines and check all emitters (if there are too many emitters to check them all, keep on eye on each plant so you can tell when irrigation emitters may be plugged) so that your plants will be happy throughout our hot/dry summer. Lawns- lawns need water when you walk on it and the blades do not spring back up. Water in short burst rotation-ex: 5 minutes water, rest fifteen minutes, 5 minutes water, repeat a few times. This allows time for the water to soak in and prevents run off. Roses-most roses (especially hybrid tea roses) do best with regular watering.  
• Pruning - After the flowers fade from spring flowering shrubs, if needed you can prune Lilac, Rhododendron, Azalea, Camellia, Forsythia, Ribes, and Flowering Almond. There are different types of pruning depending upon what your intention is for your plants. When you would like to improve your confidence for pruning Contact Mary for a Consultation/Tutoring Appointment. Ferns - if you have not pruned out the old fronds from your ferns prune now. Follow all the dead fronds down to the base of the stem and cut out the entire frond; being careful not to cut the new growth or accidentally break new fronds off. Fuchsias – As the Fuchsia fills in, pinch out tip growth to encourage more branching, which means more flowers later. Watch The Gardening Tutor Video: How to Prune Fuchsias. 
• Fertilizing - After the flowers fade from Camellia, Rhododendron, and Azalea, fertilize with an acid fertilizer so they get a good start on the year it takes for them to form next year’s flowers! Gardenias appreciate regular fertilizing to keep flowering throughout the growing season. Use an acid fertilizer once a month for in ground plants and every two weeks (at half strength) for container Gardenias. (If your gardenia flowers turn brown before opening the plant may have an infestation of thrips.) Blueberries will appreciate some acid fertilizer this month too! Blueberries are great for large containers. Mulch blueberries with redwood compost and they will love it! Watch The Gardening Tutor Video: Two Quick Methods to Apply Liquid Fertilizer.  
• Fruit trees - Although there is a natural thinning of fruit in nature referred to as “June drop”, it’s still a good idea to thin fruits a little before June drop. After June drop you can thin some more. The most important reason for thinning fruit is to lessen the weight on the branch so that you do not come out to your garden one morning and see an entire branch on the ground and a big gaping wound in your fruit tree. The other reason is to encourage bigger and more healthy fruit!
• Weeds! For more about how to manage weeds Watch The Gardening Tutor video: Weeds, How They Grow and How to Manage Them.
• Container Plants -Apply at least a one inch layer of compost as mulch to container plants. Now is a great time to empty the potting mix from containers and replace with new mix. Also, add water holding polymers to help hydrate plants this summer.
• Pest Management - Control ants with bait. When you see ants crawling up and down your fruit trees, ornamental shrubs and other plants this is a sign that your plants may be infested with aphid or other insect pests. First, control the ant population. Also, wash off the aphids with a strong stream of water. If the infestation is still heavy use insecticidal soap (remember the follow up spray 7 to 10 days later-follow directions on the bottle). Sometimes, if you control the ants, the beneficial insects will show up to control those aphids and other pests for you.  
• For More May Tips go to Gardening Tips for May 2025. 

• When you're ready to learn how to care for your plants  Contact The Gardening Tutor
   

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ALL CONTENT and Photos by Mary Frost (no AI).