If you want your trailing petunias to create long, dense trails out of baskets and containers, they need at least 6 hours each day of direct sunlight.
Of course, you can plant them where there is less direct sunshine, but their growth will be less rapid.
Drainage is also crucial, so lift any ground-based pots or containers with pot feet to prevent root rot.
How to Deadhead and Prune Trailing Petunias
Deadheading a plant does two things:
- to organize the plant and make it look better.
- to stop plants that set seeds from “going to seed. An annual plant frequently stops growing after it begins to produce seeds because it has fulfilled its reproductive function. By deadheading and preventing the plant from developing seeds, this can be avoided and growth can be prolonged.
A short Google search turns up dozens of authors who assert that if you want lengthy, dense trails, you should deadhead trailing petunias as frequently as you can.
There are various petunia types, such Wave and Surfinia, which grow well with relatively minimal deadheading and are ideal for the time-constrained gardener.
Regular deadheading (at least once a week, but ideally twice a week) is advised for the majority of other varieties of petunias.
Make sure to remove the seed pod along with the blossom after deadheading.
Pruning
One of the most crucial chores is pruning, but it’s sometimes ignored or done improperly.
When a stem is cut, side branches emerge and eventually grow into new stems.
The few stems you have will grow long and lanky with few side shoots and blooms if you don’t prune enough or forcefully enough.
We advise deadheading petunias once a week and trimming back any long, lanky stems to promote side-shoots that will trail. Start by trimming any stems that are frail or have few blooms or leaves.
When pruning, try to keep a uniform shape, but if the plant is a little lanky and sparse, don’t be afraid to remove half or more of the growth.
You can simply go ahead and forcefully trim back your plant to just below the rim of the basket or container if you believe it is already too far gone and is severely neglected, lanky, and lacking in blossoms. Always fertilize regularly after any vigorous trimming to promote growth.
How to Avoid “Flat Topping
Not only will the ideal petunia hanging basket or container have long trails, but it will also have a well-rounded top part with blooms and lots of leaves.
The top of the basket will appear flat and sparse if you let all of the stems in the center of the basket grow long and overflow the edge.
Simple pruning of the lanky stems to promote bushy growth near the top of the basket or container will easily stop this from happening.
Just go ahead and aggressively trim away any neglected trailing petunias until there are about 12 inches of the plant protruding over the edge of the basket. The plant will grow quickly, and much of it will be in the top part.
How Often Should Trailing Petunias be Watered?
Here is how often we water the containers and baskets we use for petunias:
- Summer days that are overcast, cool, and gloomy occur every two to four days.
- Every day or every other day in the heat, typical daywater.
- Very hot summer days, especially in the morning and evening.
Petunias need a lot of water, yet the roots prefer a soil that is damp but never soggy. Additionally, the baskets or containers should have a bottom that freely drains water.
If you water the basket and it starts to drain out the bottom right away, it’s likely that the soil is too dry and has contracted, and the water is just fleeing through the cracks. To fix this, water the plant, let it sit for 15 minutes to allow the soil to swell, and then water it once more. Moving forward, make an effort to stop the soil from drying out to the point where it shrinks.
Can petunias be overwatered? Yes, root rot is a possibility, but it typically only arises when a container or basket lacks drainage holes or when the potting soil is so dense that the water cannot escape. View the potting soil and baskets we recommend at the top of this page.
Even though it has been raining, should you water the petunias? It’s unlikely that a brief summer shower would be sufficient because we often water our petunias heavily. So we continue to water them even after it has rained. Although many are positioned beneath the roof overhang, which shields them from the majority of the rain, baskets and containers are frequently quite small and only catch a small amount of rain.
You must be careful not to drown the plant by flooding the roots if your basket or container has just one or two drainage holes.
Fertiliser and Feed
Every gardener will have a different answer when you ask them how frequently they fertilize their petunias. Nutrients that are flushed out of hanging baskets by watering need to be renewed, however there is no defined schedule.
Unfortunately, even plants in hanging baskets might receive too much fertilizer. Yellow leaves and stunted growth can result from having too much zinc, manganese, copper, or phosphorous, which can prevent iron from being absorbed.
Petunias grown in baskets should be fertilized every week. Therefore, every seventh watering will be required in the summer when you water once daily.
Since you won’t be watering as frequently and the nutrients won’t be washed out of the basket as frequently during cooler times, you can cut the frequency to around once every ten days.
Of course, fertilizing every two weeks will still yield fantastic results, but we believe applying more regularly will result in better development.
You won’t need to fertilize petunias in flowerbeds or the ground as frequently. Petunias planted in large containers don’t require as regular fertilization either.
Keep in mind that summertime drying out can cause baskets to require more watering. More fertilizer is needed to replenish lost nutrients the more water is used.
Watch out for symptoms of overfertilization like yellow petunia leaves. If that occurs, turn it down and give the petunias some iron that has been sequestered.
Best Fertiliser For Petunias
Starting with an excellent all-arounder like Miracle-Gro soluble universal fertilizer, which has a high concentration of nitrogen and is ideal for promoting long trails, is what we advise.
If you see that the petunias are a little lanky and are producing few or small blooms as the season progresses, you can replace the occasional feed with fertilizer that has a higher ratio of phosphorus.
In order to preserve the petunias’ leaves lush green, we also advise giving them a monthly dose of sequestered iron.
With the use of this product, we were able to restore the petunia foliage to a vibrant green color.
How far apart should trailing petunias be planted?
All petunias require average, slightly acidic to neutral soil with a pH of 6.0 to 7.0 at a location with at least six hours of direct sunlight each day and more, if possible. Peat moss, aged manure, or compost should be added to the soil at a depth of 2 to 3 inches and then thoroughly worked into the soil until it reaches a depth of 8 to 10 inches.
According to the Old Farmer’s Almanac, the area should also have good drainage because petunias thrive badly in too-wet soil. While multifloras only require a spacing of 4 to 6 inches, grandifloras and multifloras both require planting at a distance of 12 inches. Petunias that spread or trail should be planted at least 1 1/2 feet apart, even if they only reach a height of 6 inches.
In a hanging container, how are trailing petunias planted?
Petunias thrive in regions with direct sunlight. Look for petunia varieties that produce flowers on long, flowing stalks, such as cascading petunias. Petunias are simple to plant in hanging baskets as long as you choose a robust container with at least one drainage hole.
A light-weight commercial potting mix should be used to fill the container because it will help the drainage. Never use garden soil because it soon compacts and is too heavy for adequate drainage. When planting, incorporate a slow-release fertilizer into the potting soil.
Can you plant trailing petunias in the ground?
Petunias can be grown from seed, purchased as little plug plants to grow on, or purchased as plants that are ready for the garden. Because petunias are delicate and cannot withstand any frost, you must wait until late spring or early summer to plant them outside.
A good, rich soil is necessary for petunias to grow well. Before planting, prepare the soil in borders by incorporating a lot of well-rotted compost or soil conditioner. Petunias grow best in multipurpose, peat-free potting compost for pots and containers. Choose a compost that has water-holding granules for raised containers like hanging baskets and window boxes that are exposed to drying sun and wind.
Petunia spacing is greatly influenced by their development pattern, final size, and the environment in which they are produced. Plants can be crowded closely together in pots and other containers to create a stunning display quickly. The smallest compact and upright kinds can be planted as close together as 15-20 cm; bushy petunias with a loose, mounding habit require a wider spacing of about 30 cm; and trailing varieties require a spacing of about 40 cm.
Petunias should be gradually acclimated to the outside for a week or two before being planted outside. When purchasing garden-ready plants, make sure they haven’t been kept in a covered area or in the event that they have, they will need to be hardened off before planting.
Where to grow petunias
Petunias require a lot of sunlight, rich soil, and protection from wind. Petunias will also thrive if given some shade in regions of the country with hot summers or milder climates.
Because of their extreme adaptability, petunias can grow in practically any kind of pot or container, regardless of size or shape.
Petunias that trail off the sides of pots or window boxes make excellent plants for hanging baskets, raised pots, or window boxes. They can be planted to tumble down slopes, banks, and from raised beds, and they create a distinctive and vibrant ground cover in borders.
In a colorful bedding arrangement, as a splash of bright color amid the perennial plants in a border, or as part of bushy, upright arrangements in pots or planted in the ground, petunias make excellent displays.
How to care for petunias
Petunias grown in pots and containers require regular watering, which is crucial. Avoid letting the compost dry out, but also be careful not to overwater it because this can result in spindly growth. During dry seasons, petunias planted in the ground also require watering.
To prevent sunburn on the tender leaves and huge flower petals, direct the flow of water onto the earth rather than showering the plant. In order to avoid burning, try to water in the early morning or late at night when it’s hot outside.
Feed plants with a potash-rich liquid fertilizer every 10 to 14 days in the summer and early fall (such as tomato fertilizer). Switching to a high-nitrogen fertilizer can accelerate growth for the final few weeks before the frosts if plants start to look drained in the fall.
Petunias appear better and produce more flowers when fading and dead flower heads are removed. Later in the season, trailing kinds that start to look straggly can be softly clipped. Feeding simultaneously will encourage new growth.
How to propagate petunias
Although they are not the easiest of plants to propagate, petunias can be produced from seed. When the temperature is 21C in late January, seed should be sowed. Petunia seeds need light to germinate, so don’t cover them. Instead, sow them on the surface of moist compost and cover them with polythene or place them in a propagator to keep them from drying out. Seedlings require a warm, well-lit, shaded habitat that is between 13 and 15 degrees Celsius.
A excellent middle ground between starting from seed and purchasing more expensive garden-ready plants is to purchase petunia plug plants. Early to mid-spring, mail-order plug plants are available. Plant them out only after hardening off and when all threat of frost has passed in individual 9cm pots and growing on a well-lit windowsill or in a heated greenhouse.
If pruned and transferred into a warm setting, some petunias, primarily trailing kinds, can be retained during the winter. If you don’t have much room, root cuttings in the late summer, pot them up separately, and store them indoors on a ledge for the winter.
Growing petunias: problem solving
Given the proper growing conditions and maintenance, petunias are often trouble-free. Young leaves and stems may develop aphid infestations; you may prevent this by checking your plants frequently and manually eradicating any tiny infestations. To control aphids, there are a variety of ready-to-use sprays available.
Snails and slugs can be an issue, especially for petunias that are rooted in the ground. Before putting petunias outside, grow them to a good size because larger plants are far more equipped to survive attack. Use an eco-friendly bait or surround plants with absorbent granules or barriers.
What occurs if petunias are planted too closely together?
Kole claims that if you place flowers too closely together, the plants get stressed and more susceptible to disease. Fungus develops if air cannot flow freely and the plants cannot dry out between waterings. The roots may decay. Insects then invade plants that have been stressed out.
In order to maintain a healthy distance between flowers, Level Green personnel will clip some plants as they mature if you decide to place them excessively close together.
Petunias can be planted closely together.
Petunias should not be transplanted into the garden until the ground has warmed to about 60F and the risk of a frost has passed.
Grandifloras and multifloras should be planted about 12 inches apart in full sunlight, or a few inches closer apart in a more shady environment.
Petunias that spread and provide ground cover should be planted at least 1 1/2 feet apart.
Petunias need to be planted significantly closer together in containers in order to appear full and lovely from the beginning.
If it’s hot or windy with few clouds when you’re transplanting, consider offering some cover from the midday sun for the first several days. Pinch back grandifloras or multifloras when they reach a height of around six inches to promote the quick development of flowering side shoots. Avoid pinching or “spreading” millifloras or petunias.