A wet season marked by multiple atmospheric rivers gave way to Instagram-perfect green hillsides, superblooms and refilled reservoirs. But for homeowners and gardeners, challenges remain.

Experts say that while trees, shrubs and other plants benefited from all the rain, the cold and wet weather has also made plants develop more slowly and bloom later, as well as encouraging weeds. And gardeners will still want to take steps to protect plants from the hot and dry weather to come this summer — and beyond.

wSo here are some areas to keep in mind:

Watch out for weeds, diseases and pests

Janet Hartin, a UC Cooperative Extension environmental horticulture adviser, said that when weeds produced seeds in recent seasons, drought-parched soil layers prevented the seeds’ germination. But they were still viable when the rains came.

“Now we have this perfect storm,” she said.

For keeping weeds at bay, Hartin recommended using a mulch of some kind. She said organic mulches such as wood chips or wood shavings should be put in planter areas in 3-4 inch layers. Inorganic mulches such as gravel or pebbles can be put in 1-2 inch layers, since those materials form a tighter surface that lets less light in.

Hartin said mulches have the added benefit of keeping moisture in the ground.

There may also be more invasive insect and disease pressures for gardeners to contend with. Hartin said keeping plants healthy and well-tended will help stave off disease.

But disease may be less of a threat than before, Hartin said.

In the past, trees and shrubs were weakened going into spring and summer because of drought, but that’s not the case this year.

“The plants have better protection because they’re already healthier,” she said.

Gardeners who need help diagnosing a pest or disease have some options at their fingertips, Hartin said.

The University of California Integrated Pest Management Plant Problem Diagnostic tool (ipm.ucanr.edu, search “diagnostic”) can help gardeners figure out what’s wrong with their edible and landscape plants. Users can search by plant name, type or symptoms.

The International Society of Arboriculture has a list of certified arborists who can provide expert help with tree problems at isa-arbor.com. This may be a good option for people with prized trees that are older or larger, Hartin said.

Lastly, the University of California Master Gardener volunteers are available to answer questions through free email and phone helplines at mg.ucanr.edu (search “program coordinators”). These services are available in all Southern California counties.

Don’t be daunted by late blooms or stunted plants

Exequiel Ezcurra, a professor of ecology in the department of botany and plant sciences at UC Riverside, said this spring was not only unusual for all the rain but for the cooler temperatures that persisted through late April and early May. He said evidence of the cooler weather is visible in trees that are tropical in origin: Jacarandas, tipuanas, coral trees and others are not forming blooms as early as they normally do. Even native plants such as the Southern California flannelbush are blooming later than normal.

Ezcurra said that if a tree or shrub that blooms typically around this time of year hasn’t yet, it likely will — just a little later than usual.

Some spring and summertime veggies may be stunted, too, according to Ezcurra.

He used the example of a garden that he maintains with his wife that has corn, beans and squash. He said those things, planted in late February, have not taken off like they normally do. The corn, which would normally be ready by June, is less than 2 feet tall.

But Ezcurra said there’s still plenty of time to grow summer veggies. If those varieties haven’t been planted yet, they can be now.

For those who have planted summer vegetables already and find that they’re a little lackluster, Ezcurra’s advice is to wait.

“Just water them because now that we’re getting the heat coming in, they will grow and develop,” he said.

it’s time to plant trees

It’s not just a good time to plant summer veggies.

Hartin said she always recommends that people look at their yards and consider whether they have space for a tree because of the cooling effects trees have on urban heat islands.

There should be about 15 feet of space around the planting site, and Hartin recommends climate-resilient species such as desert willows, mesquites and chaste trees.

Hartin said gardeners who want to plant a tree should do so in the next two to three weeks, or wait until fall when the weather has begun to cool.

Be aware that your plants will still be thirsty

It’s already getting a lot warmer and there are some indications that it could be an average or slightly warmer than average summer, according to Ezcurra.

For trees, he said, that may not mean much yet because there’s still lots of water in deeper layers of soil, but annual plants with shallow root systems will soon need supplemental water from a sprinkler system if they’re not already getting it.

As the summer progresses, shrubs and trees will start drawing from those lower soil moisture levels.

Hartin said July will be the month of highest water demand, and it will be important to deeply irrigate these plants. She said they should be allowed to dry between waterings to avoid disease-causing fungi.

Hartin also noted that while much of Southern California is no longer in a drought, we’re not out of the woods yet.

While rainfall was considered average for places such as coastal Orange County, dryer-than-normal conditions persist in much of Riverside and San Bernardino counties, and desert areas are still in drought.

“I think we need to set our expectations with an eye on, ‘Could this continue?’” Hartin said. “And I think that it’s likely the drought will continue.”