We may earn a commission from links on this page.

If you need a reminder that summer has finally landed, berries are here to remind you. Home gardens are spotted with tiny colored jewels of strawberries, currants, and oso berries. Cherries, raspberries and blueberries are beginning to blush with color as they ripen, just as the peonies and irises fade. Peas are popping off of tall vines, nasturtiums have begun to sprawl across garden beds, and spring-planted spinach and chard are sky high. This is your first chance to enjoy the spoils of your summer garden.

Cherries, blueberries, and raspberries about to ripen. Credit: Amanda Blum

Pruning and trellising

Within two weeks of your lilacs finishing blooming, you should consider pruning them back. This is when plants will determine blooms for the next season, and in some lucky cases, you can spur a second, fall bloom. You want to take as much as ⅓ of the plant's stems, so you encourage new growth each year. This is the case for all your early summer blooming shrubs and trees, like azalea, forsythia, Japanese kerria, weigela, deutzia, mock orange, St. John's wort, viburnums, and red or yellow dogwoods.

Lilac after blooming Credit: Amanda Blum

The pruning should extend to your tomatoes, now established in the ground. You’ll want to prune for suckers, depending on what kind of trellis system you have set up. If you’re allowing indeterminate tomatoes to only have one strong “leader” or stem, prune aggressively, but you’ll need tall trellises. Also be sure to cut away any diseased parts of the plant, but remember you only want to touch your tomatoes after the morning dew has dried, and with clean shears. Spray with Lysol or other disinfectant in between plants, so you are not spreading any disease. 

Tomato plants growing in trellises. Credit: Amanda Blum

Once your strawberries are done fruiting, mow them back and mulch them, so they won't continue to spend their energy growing runners, but will focus on root growth for next year.

Fruit-thinning

Fruit drop is when a tree drops fruit it cannot support (left). The remaining fruit, on the right, ripen. Credit: Amanda Blum

Your pears, apples, stone fruit—like peaches, plums, cherries and nectarines—and even fig trees will have set fruit by now, and also gone through fruit drop, a normal phenomenon where the trees drop what they can’t handle. With the fruit still on the tree, you must decide on quantity or quality. Thinning the fruit on each branch will allow the tree to create larger, tastier fruit. You can also shroud the fruit at this point, covering the fruit with gauze bags, to protect it from invasive bugs or animals. The same is true of grapes. Your vines should be well flushed out at this point, which means you can harvest grape leaves to use fresh or preserve for use later, and then shroud all your growing grape bunches. This will make them much easier to harvest, and also protect them from birds, raccoons, and rats.

Small grape clusters shrouded in gauze bags. Credit: Amanda Blum

Fertilizing

It’s important to not simply water your vegetables in raised beds, but also feed them. In addition to plant -pecific fertilizer (tomato fertilizer, blueberry and azalea fertilizer, etc.), you should consider a weekly treatment of compost tea. If you don't have a vermicomposter to make your own compost tea with, purchase compost tea bags and make some. Apply the tea with a sprayer folicularly (over the whole plant). Your tomatoes can also benefit from a treatment of Cal-Mag or Rot Stop, which will provide the plant more calcium to help prevent tomato blossom rot on forthcoming fruit. With most asparagus done harvesting by June, apply a nitrogen-heavy fertilizer for next year. 

Your lawn should get a low-nitrogen-based fertilizer in June. Your roses should get a phosphorus-based fertilizer treatment after their first bloom, which should be about now. All your trees and shrubs should get a summer fertilizer before July 4. Your garden center can help you find the right fertilizers, since not all plants should get the same one—and fertilizer is heavy, so you'd do well to buy it locally instead of have it shipped to you.

Preventing and eradicating pests

Cabbage moths. Credit: Amanda Blum

Garden pests are absolute terrorists this time of year. Just this morning I noticed many bean seedlings peeking through the soil had been thwarted by slugs. Sprays won’t be the only solution at this point—you’ll need to manually remove the pests from your plants as well. Aphids may be sprayed off with water, but without a treatment like soapy water or a nearby trap plant like nasturtiums, they’ll be back. If you don’t have nasturtiums nearby, plant them now—the aphids will be more attracted to the nasturtiums and will choose them instead. You just leave the aphid-infested nasturtiums in place. Treatments like Sluggo can help reduce the slug population, but manual extraction is still necessary. Leave shallow lids of beer or yeasty bread starter around as a trap, and collect the slugs that run to it each day.

Each plant in your garden has a number of pests that are trying to feed off of it; a daily walk around your garden will help you notice what might be attacking your plants. Get a butterfly net, and use it to capture and kill the white cabbage moths flitting about the garden.

Dealing with sick plants

Diseased leaves on a cherry tree. Credit: Amanda Blum

Gardens are highly susceptible to virus and fungus; one of the best ways to prevent them is to water at the root of plants, rather than overhead, which splashes onto the ground, causing water to spray back up onto plants. As you see blight or mosaic virus in your garden, you must cut it out quickly, dispose of those plants in the trash (not compost), and be sure you wash your hands and tools before moving onto the next plant. If you see powdery mildew on your plants, you can treat it with a diluted vinegar spray. Now is when you might catch sign of infections like leaf curl on your stone fruit trees, which can be treated if caught quite early with copper foliar sprays. Fungicides can go a long way to helping prevent problems like black spot on roses. You want to be very judicious when using fungicides and copper sprays: These are mostly preventative treatments, not reactive. If you’re questioning what you see in your garden, take a picture and head to the garden center. 

What to plant

The summer vegetables should all be in the ground by the end of June. Your tomatoes, eggplants, peppers, and tomatillos need to be planted in early June, and if the weather hasn’t met planting conditions yet, you need to consider putting mitigations like Agribon in place and planting anyway. The Agribon tenting will create the warm conditions you need, and you can remove it when temperatures get warm enough on their own. 

Beans, cucumbers, corn, edamame, eggplants, melons, okra, summer squash, and sweet potatoes should get planted this month. If it’s early enough, they can still be direct seeded, but by mid-June, you should plant starts instead.  

Sweet peas. Credit: Amanda Blum

You can still plant almost all your summer annual flowers, including zinnias, cosmos, sunflowers, salvia, and celosia from seed or as starts. Planting them in waves ensures multiple successions of flowers later in the season. Remember when planting these flowers to check seed labels for heights, so you can vary them. 

Now that your spring flowers are wilting, deadhead them appropriately. Your tulips need to have just the heads cut off, but no lower—remember they need leaves to mulch in place to return next year. Iris stems may be cut to the ground, but in a chevron, to ensure good growth next year. If you commit to religious harvesting of your sweet peas, you can make them last well into the summer. Each day, cut fresh blooms at the base of the stem, and you'll notice that the stems get shorter and shorter. Once the sweet peas go to seed and produce pods, it's time to pull the flowers out of the ground and plant something else. Deadheading your snapdragons will encourage the plants to branch, creating more blooms, but as soon as the snaps go to seed (the flowers will look like skulls), they should be cut to the ground, in hopes they might return the next year.

Through June, the best course of action is to take a walk through the garden once a day, even if it’s a quick one. Each morning, I wander the garden, grabbing weeds as I find them. Harvest what you can, take note of action items like pests or pruning, and be sure to take pictures and write in your garden journal. It’s the reason you planted the garden: to enjoy it.