The best time to plant annuals is generally after the average last frost date. Pay attention to the forecasts to determine if you need to wait longer. If transplanting to containers, you can plant them earlier and bring the pots indoors if there is a risk of frost.
Is it ever too late to plant your annuals? The answer is no. While there are certain times that are optimal, if you are busy during the spring, you can certainly start and still grow some magnificent annuals starting in the summer.
Since most annuals are frost tender, you'll need to wait until after the last spring frost date to transplant them into your garden.
Temperatures below 32 degrees can freeze the leaf tissue of cold-wimpy plants and turn them to mush after just a few hours. Some of the most tender annuals and veggies might not die but suffer cold-induced setbacks even when overnight lows dip below 40.
Some cool-season annuals can tolerate soil temperatures as low as 45 degrees Fahrenheit; however, most cool-season annuals will grow best in soil temperatures at 65 degrees Fahrenheit or warmer.
Winter time is very hard on flowers. They just do not like any temperature below freezing. Don't get me wrong flowers like it cold. Flowers are happiest in temperatures of 40-50 degrees.
Most flowers should be planted after your region's last frost date. Planting flowers in spring is the most popular time, but perennials do fine if planted in early fall in the North and late fall in the South.
In general, wait until the temperatures range from 60 to 70 degrees Fahrenheit to plant tender vegetables like corn, tomatoes, peppers, eggplants, okra, summer squash and beans. Use a soil thermometer to make sure the soil is warm enough to plant.
Many annuals need full sun to produce their biggest and best blooms. Others, like begonias and polka dot plants, don't require full sun all day, but they still need a few sunny hours.
In fact, many plants — such as spring bulbs and perennials — need to be planted in the late summer or early fall months, depending on your zone, in order to generate enough energy to bloom in the spring. Not to mention, it's never too late to add some colorful annuals to your outdoor space!
Annuals, with their shallow roots, will typically need water every single day. Especially if they're in the hot sun. On those hot sunny days water your annuals twice a day. Don't let your annuals dry out, especially if they're in a container.
While you can plant a late planting to the first frost date, it's always best to allow as much growing time as possible. If you missed the spring planting, then calculate which vegetables you can grow now and still have a harvest before the first frost.
The hardiest of flowers can be planted as soon as the soil in your garden can be worked, even if it's several weeks before the last frost of the season. For half-hardy flowers, hold off until a couple weeks before the final frost, and for tender flowers, plant when there's no chance of frost for the rest of the season.
Plants that thrive is the heat of the summer prefer to be planted in warm soil. Most annuals and vegetable should be planted when the soil is 70 degrees. The average soil temperature for the last five years on May 1 is 62 degrees.
Work the soil when it is moist, but not wet. Turn the soil over to a depth of at least 12 inches. Add 2-3 inches of compost and turn it into the bed. Either cover the bed with a thick (3-4") layer of mulch or use a weed and feed to help keep weed seeds from germinating.
Good choices are summertime kitchen garden staples like squash, beans, cucumbers and melons. Beans (Zones 3-10): You can plant both bush and pole beans now that the soil and air are warmed up as beans should not be started indoors. Try a continual 7-10 day sowing of different varieties.
It's never too late. It just matters what you put into that garden. It's too late to grow tomatoes in your Chicago garden in September because you'll be getting cold weather soon, but you could still grow carrots, radishes, and lettuce plants.
I did some research and found out that houseplants need to be taken indoors before overnight temperatures dip below 45 degrees. Most tropical plants suffer harm from temperatures below 40 degrees.
It's best to wait until the last freeze of the season has passed before planting anything outside. Typically for the DMV the last freeze of the season occurs between the last week in March and the first week in April. A good rule of thumb is to wait until Mother's Day to plant anything outdoors.
The general rule of thumb is that most plants freeze when temperatures remain at 28°F for five hours. Of course, there are exceptions to this rule. Seedlings, with their tender new leaves, often give up the ghost when temperatures dip to 32-33°F. Tropical plants have differing low-temperature thresholds.
Gardening in the fall provides a longer period with more 'good' days, as compared to the often tumultuous spring season. Plus, if you plant in fall you'll end up ahead of the game and won't have to rush to get everything done after winter. In fact, a good strategy is to plant perennials when you plant your fall bulbs.
The Basics of Planting Annual Flowers
Tender annuals — Tender annuals thrive in warm soil and warm air temperatures. They should only be planted once temperatures reach and stay above 55°F. They can be severely damaged or die if they are exposed to frost or temperatures below 32°F.
The best month to plant flowers in spring is really down to the USDA hardiness zone you live in and the likely last frost date. This is likely to be from around March, but if you live in a northern zone, be sure to plant frost-tolerant perennials until you are happy that the risk to more tender flowers has passed.
However, know that even if air temperatures are as high as 38°F, frosts may occur on the ground and on plants. It's better to protect plants just in case!