For The Union-Tribune
Warm/cool/warm/cool … June weather can be all over the place, from overcast gray “June gloom” drizzles to bright, hot sunny skies. Whether you live along the coast, in the mountains or in the desert, June temperatures are warmer overall, but how warm and how sunny changes from day to day.
Vegetable gardens
This is when vegetables are the garden’s focal point.
• Ready to up your tomato growing game? my tomato growing guide here: bit.ly/tomatoesguide.
• If your tomatoes, eggplants, peppers, etc. are not yet producing, don’t worry. As temperatures increase, so will flowering and fruiting.
• Squash confidential: zucchini, summer squash, winter squash, melons, pumpkin and cucumber are all closely related and grow the same.
− If you see lots of flowers but no fruits, just wait. Plants in the squash family typically produce male flowers for several weeks before they begin to produce the female flowers that become the fruits.
− Female flowers are always swollen at the base. The swelling becomes the fruits once the flower is pollinated.
− If your plants develop small squashes, cucumbers, etc. that turn brown at the tip and fall off, chances are, the fruits began to develop even though they weren’t pollinated.
− If both male and female flowers are present, try hand pollinating using a cotton swab or small watercolor brush.
• If there’s still space in your garden, start a new round of tomatoes, cucumbers, squash, eggplants, basil and so on. Plant now — from seed or seedling — for harvest late summer/early fall.
• Resist overplanting. Crowded plants grow into a jungle that reduces production and makes plants vulnerable to insects and disease.
• Pinch flowers and flower buds off seedlings before planting seedlings.
• Good air circulation prevents powdery mildew (white powder on leaves). Selectively remove plant branches to improve airflow. Also, rinse leaves with water early in the day to wash away mildew spores. Do it early enough for leaves to dry by late afternoon.
• Remove the lowest tomato leaves and branches to prevent soil fungi from infecting the plant.
• Don’t follow advice to prune tomato plants. The leaves photosynthesize. They are the plants’ powerhouse. The more leaves, the more energy a plant makes to form flowers and fruits. Removing leaves limits the energy and the flowers/fruits a plant can make. For lots of fruits, leave the leaves.
• Mulch vegetable plants with a thick layer (3 or more inches) of straw — NOT hay, not bark, not wood.
Fertilize vegetables:
• Feed vegetable plants with organic vegetable fertilizer. Mix fertilizer into the entire garden bed before you plant. Add a bit more fertilizer to the planting hole, then fill the hole with water before you plant.
• Through the season, pull the mulch back; sprinkle fertilizer over the soil, water, then replace the mulch. Follow label directions for how much and how often.
• OR add liquid fertilizer to your irrigation water — this process is called “fertigation” — half strength every time you water.
• ALSO use liquid fertilizer as a quick fix foliar spray for plants showing signs of nutrient deficiency.
• If you see skeletonized tomato leaves and tiny black or deep green balls, look for tomato hornworms. The caterpillars are green, white and black striped. In their larval form, they devour tomato plants but as mature sphinx moths, they are important garden pollinators. Consider growing a sacrificial tomato plant and letting the worms go through their life cycle on that plant. That’s a win-win!
• Skeletonized sunflower and squash leaves are the work of tiny birds called lesser goldfinches. Those birds also eat aphids, so welcome them to the garden.
• Avoid tomato and squash blossom end rot by keeping soil damp (not wet) at all times. In some regions, blossom end rot is a calcium deficiency, but in our climate and soils, it results from uneven watering.
• Trellis cucumbers to keep the vines off the ground. It makes the fruits easier to find, too.
• Plant cilantro in the shade of cucumber trellises. They’ll produce more leaves, for longer, in a bit of shade
• Give watermelon, pumpkins and vining squash plants plenty of room. The vines of a single plant can easily cover a space 20 feet long by 20 feet wide!
Fruit trees
• Protect fig fruits from the black fig fly. As soon as the tiny fruits form, cover branch ends with drawstring mesh bags. Those bags protect the fruits from rats and green beetles, too.
• Fertilize stone fruit, apple, pear and persimmon trees with organic fertilizer, following label directions. Water regularly and deeply during the fruiting and growing season.
• Fertilize citrus and avocado with granular, organic citrus and avocado food. Water citrus deeply, every few weeks. Water avocado deeply once or twice a week.
• Pomegranates, figs, tropical guava and pineapple guava don’t need fertilizer but are best watered every two or three weeks, depending on the heat.
• Too many ripe fruits? Halve them, remove seeds or pits, then freeze for winter cooking. to label and date the containers.
• Share your extra harvest with those in need. organizations that pick and donate fruit to food banks and other feeding programs. Find lists of gleaners for your county online. If you have time, volunteer to help — it’s fun!
• Clean up fallen fruits and practice good garden hygiene to avoid attracting hungry birds, green fig beetles, squirrels, rats, etc. Harvest fruits as they ripen, before they rot.
Ornamental plants
• Drought-tolerant shrubs need little care this time of year. Groom to remove dead flowers and spent leaves. Keep them mulched and water deeply only once every few weeks.
• Container plants need more attention in summer. Fertilize nonsucculent potted plants with an all-purpose organic fertilizer (liquid indoors, liquid or granular outdoors), following label directions.
• Potting soil dries out much faster than dirt. When it’s time to water, do so slowly to saturate the entire pot, soil and all. Wait until the water drains out and then do it again. Sit lighter weight pots in a basin of water and let the water wick to the top.
• Repot and refresh potting soil for longtime potted plants. Top off with new a sprinkle of worm castings and some organic, granular all-purpose fertilizer. Top the potting soil with small pebbles for a finished look and to keep away fungus gnats.
• Move sun-shy potted plants like Fuchsia and orchid cactus (Epiphyllum) under the shade of a leafy tree or an east-facing eave.
Manage wildlife
: Wildlife has a place in every garden. Plants are not perfect. They aren’t supposed to be.
birds and bees through the warm weather.
• Fill a shallow dish or birdbath with water.
• Add a solar-powered floating birdbath pump that sprays water to keep it recirculating. Moving water keeps mosquitoes from breeding.
• Add small pebbles, glass marbles, etc. for birds and bees to perch on as they drink.
• Check regularly so the water stays clean, and the pump doesn’t clog.
Insects and other tiny garden critters can be unnerving but are seldom a problem. A few pests in the garden make sure natural predators stick around. Your goal is to the cycle to keep your garden in balance.
• Caterpillars and worms nibble on leaves but seldom kill plants. While a few aren’t an issue, if they are truly decimating your plants, pluck them off and leave them in an open area where hungry birds and lizards can find them. Birds and lizards are nature’s pest control!
• Control snails, slugs, and roly polies (aka pill bugs) with Sluggo Plus, an iron phosphate product that is not toxic to birds, mammals (including us), caterpillars, butterflies, etc.
Manage water
Thanks to winter’s generous rainfall, we don’t start summer in drought, but chances are, we’ll finish in drought, so stay vigilant when it comes to water management.
• Inspect your irrigation system zone by zone. Turn on each zone (each irrigation zone is controlled by a single irrigation valve). Check all drip lines and sprinklers. As you walk the zones, watch for leaks, broken heads, overspray, etc.
• Don’t overwater. Winter’s extra rain doesn’t mean your plants need — or even want — more water.
• Collect cold bath and shower water in a bucket. Use the water for potted plants, thirstier tropical fruits, and vegetables.
• Mulch, mulch, mulch; but only if you have a drip irrigation system.
• Spray irrigation is not compatible with mulch. Too much water is wasted saturating the mulch before it can saturate the soil where the roots are. This is another reason to switch out spray irrigation for inline drip irrigation, not for individual emitter irrigation
• As the summer temperatures warm, deep-water big trees once a month. Even drought tolerant trees need a long drink to survive.
Trash the grass
Grass is the thirstiest plant in our gardens and the one least often “used.” Summer’s long, warm days are the best for removing or reducing your lawn. Plan now.
• Check your local water agency for latest lawn removal rebates.
• Solarizing is an easy and very effective way to kill your lawn. Watch this episode of “A Growing ion” to see how its done: pbs.org/video/growing-ion-bye-bye-grass-how-remove-your-lawn.
What to plant in place of lawn?
• A colorful, flowery, drought-resilient garden like those in my latest book, “Hot Color, Dry Garden” (waterwisegardener.com/shop).
• A meadow of flowy clustered field sedge (Carex praegracilis) looks like grass but isn’t. Takes sun or shade, mowing or not, little water and feels great on bare feet.
• Kurapia, the trade name for Lippia nodiflora, which grows into a flat green surface with tiny white flowers. Warning: This plant spreads! Surround it entirely with concrete to keep it under control. Neither wood, plastic, nor metal edgings contain Kurapia.
What NOT to plant in place of lawn?
• Artificial turf (aka synthetic grass). Plastic “grass” heats up to the extreme in summer, needs regular washing, fills landfills as waste, releases microplastics into the environment, and destroys the soil along with all the critters living in the soil. Living plants are always a better choice than artificial turf.
Houseplants
Now that nighttime temperatures are above 50 degrees, move houseplants outside for summer. Place them in a sheltered spot with lots of indirect light, like a bright patio or covered balcony.
• Natural pest control: outdoors, natural predators feast on scale, mealy bugs, and aphids. If pests persist, rub them off with your fingers, a soft toothbrush, or a blast of water, from a hose or from your kitchen faucet.
• Wash down leaves to remove dust and grime that host spider mites.
• Keep plants well-watered and feed using dilute liquid fertilizer with each watering.
• Remove brown, dead leaves.
• Let the potting soil dry down so fungus gnats fly away.
• Repot plants that have outgrown their containers.
• Potting mix is not the place to pinch pennies. Your plants only do as well as the quality of the potting mix they are planted in. Get the best quality potting mix you can find — at your local independent nursery.
• Don’t plant houseplants in garden soil.
• Make cuttings now and let them root over summer.
To do, to see, to participate
June 7 through 15 is California Invasive Species Action Week. Volunteer in a California state park or the local chapter of California Native Plant Society project to eradicate invasive plants and preserve native habitats. Find information at bit.ly/InvasiveAction.
Learn all about managing your summer vegetable gardening at 7 p.m. on June 19 on Zoom. here: bit.ly/SummerVegGarden.
Want local gardening information delivered straight to your inbox? Sign up for my monthly GardenWise Garden Guide: bit.ly/Gardenwise.
Sterman is a garden designer, journalist and the host of “A Growing ion” on public television. She runs Nan Sterman’s Garden School at waterwisegardener.com.
