Gardening Tips for June 2025

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• Annuals - Lobelia erinus,  Petunias, Zinnias, Salpiglossis sinuata, Sweet alyssum, Nasturtium.  
• Perennials- Lobelia cardinalis, Nemesia, Rudbeckia, Fuchsias, Dianthus, Campanula portenschlagiana, Geum., Hanging Begonias.  
• Low Growing Shrub - Santolina, Grevillea ‘Coastal Gem’.  
• Vines - Large Flowering Clematis, Clytostoma callistegioides (Violet Trumpet Vine), Bougainvillea (planted as annual vine in most frost areas).  
• Veggies - Beets, Beans, Summer Squash, Lettuce, Basil. 
• Seeds - Sunflowers, Morning glories, Nasturtium, Cosmos.
• Extras - Bamboo Stakes, Jute Twine, Velcro Gardening Tape, Maxsea Fertilizers, Metal Stakes (Mary Uses Strong Metal Stakes from Lee Valley).

• Nemesia - Once flowers have mostly bloomed out but still have flowers on the tips, shear all the stems off (or prune stems out individually). Shear leaving lots of good looking leaves and Nemesia will repeat flower. Careful to leave the good looking leaves and not just leafless stems as the bare stems may not produce new flowers and too hard pruning may even kill the plant.
• Basil - Remember to pinch out the tip growth as the plant grows in to create a more full plant with more leaves. For best leaf flavor, do not allow Basil to bloom.
• Nasturtiums - When plants are small, water regularly to get them growing but once they are a good size taper off on the watering. Too much water makes lots of big leaves and not as many flowers. Water well but not too often once Nasturtiums really start growing. Leaves and flowers are edible!
• Weeding – Ideally, pull weeds before they go to seed. If you keep at it and keep ahead of the seeds you will see a tremendous reduction in the weed population in your garden. Weeds attract pests, like aphids and spread fungus, such as powdery mildew. Watch The Gardening Tutor Video: Weeds How they Grow and How to Manage Them.
• Neem Oil – Dahlias, Roses, and Zinnias (except the Profusion Series) all do best with preemptive sprays of neem oil to keep powdery mildew from taking hold. Once powdery mildew infects plants neem oil does not really help that much. For More About this Contact Mary for a Consultation/Tutoring Appointment.
• Pruning - Rhododendrons: Just after bloom, when the flowers of Rhododendrons have faded, carefully remove spent flowers. It may help to hold the stem in one hand and snap off the faded flower with the other hand; be careful not to snap off the new growth buds that are just under the old flower stem. Removing the spent flowers will encourage the plant to send energy into forming flowers for next year and not on seed production. Erigeron: Shear to 3 inches any time the plant has bloomed about 60 percent of the blooms. Watch The Gardening Tutor video: Shearing Plants to Encourage Flowers or Foliage Wisteria: Prune Wisteria’s vigorous growth back to six nodes (growth bumps along stem). In winter prune these same points back to two nodes to encourage flowers. If you want your Wisteria to grow longer to cover an arbor leave some of the long, vigorous growth unpruned and guide it along the area you want it to grow. Keep Dahlias and other repeat bloomers deadheaded (remove spent flower and that flower's stem) to promote more flowers.  
• Sunflowers – Sunflower seeds can be sown all summer long. Spaced about 2 weeks apart will give a continual bloomfest!  Seeds planted at the end of August here in Sonoma County will bloom by Halloween!
• Fertilizing - Clematis and repeat blooming roses appreciate monthly fertilizer throughout the growing season (Mary uses Maxsea). Also remember to fertilize citrus and other shrubs growing in containers. In ground Citrus also perform better with regular fertilizing. Continue to fertilize summer annuals, such as Zinnias, Cosmos, Salpiglosis, and others too to get them off to a good start. 
• Mulching – Camellias, Azaleas, Rhododendrons, Blueberries are acid loving plants that prefer a more acid ph mulch. Mulching helps the soil stay damp, which they all love. Annual plants tend to grow best with compost as mulch instead of bark as mulch. Watch The Gardening Tutor Video: Mulch vs. Compost.

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ALL CONTENT by Mary Frost (no AI).