It can be hard to choose the right place for dahlias. After all, they need a lot of space, and for full flowering, fertile soil is needed, prepared in advance in the autumn. Planting dahlias in pots is an easier way to grow them and occupy (beautify!) a piece of land that is not suitable for cultivation.
Starting Dahlias in Pots Indoors
These beautiful flowers can be successfully grown not only in a flower garden but also in a pot. If you plan to do this, choose varieties that have a small root system. For container growing, border, miniature, and pot dahlias are suitable.
To make dahlias in flower pots look beautiful and organically fit into the landscape of your site, choose plants that grow up to 80 cm in height.
Do not plant dahlias in large nests; divide them instead. Each nest must have a root collar, otherwise, the plant will never germinate. All thin root hairs should be trimmed. Think about how many tubers you want to plant at once — this will affect further flowering.
Planting Dahlia Tubers in Right Pots
How to plant dahlias in pots? The volume of the pot in which you should plant them depends on the size of the root system. Low-growing varieties have small roots; only 5-6 liters are needed to grow one plant. For medium-sized ones, you will need 7-10 liters, and for tall ones, at least 20 liters.
For planting, use any of the following:
- Clay pots
- Plastic pots and buckets
- Cribs and containers
- Wooden boxes.
Clay and ceramic pots allow air to pass through to the root system; they do not overheat and look very attractive. The disadvantages of such containers are high cost, fragility, and heavy weight.
Be careful when using containers in which flowers have already grown. Clay can accumulate salts and microorganisms. To get rid of salts, the pots should be soaked in water for two to three days. For protection against fungi and harmful microorganisms, pots are treated with disinfectants that do not contain chlorine.
Plastic pots, buckets, and containers look good, are light in weight, and are inexpensive. But the root system of plants growing in such a container often overheats because the roots may not have enough oxygen.
Right Size of Dahlias
Simple dahlias are represented by shrubs of different sizes:
- Small — up to 25 cm
- Medium — from 25 to 30 cm
- Tall — up to 50 cm.
The petals are arranged in one row, which is a recognizable and distinctive feature of simple (or, as they are also called, single-flowering) dahlias.
Right Fertilizer for Dahlias in Pots
When growing dahlias in pots, you must pay special attention to feeding. Even at the stage of planting tubers, the soil is mixed with fertilizers and bone meal. In gardening stores, you can buy special nutrient mixtures for flowers. Flowers need potassium and phosphorus. It is advisable to fertilize dahlias every two weeks during the flowering period, which can last from June-September.
Pinching Dahlias at the Right Time
Dahlia bushes begin to form early, even at the seedling stage. Some time after germination, when eight true leaves are growing on the plant, the top of the flower is removed. Pruning dahlias in pots can be done with a sharp pruner, clean scissors, a knife, or your fingers, gently breaking out the sprout. Deprived of the top, the dahlia begins to actively grow side stems. The bush takes on a beautiful, magnificent shape. On the side shoots, flower buds are also formed, which means that the splendor of flowering increases.
How to Deadhead Dahlias in Pots
You should not rush with deadheading dahlias in pots; they should remain in the ground in the fall as long as possible. In the autumn period, when daylight hours start to shrink, dahlias stimulate the laying of buds, from which stems will grow in spring. First, the stems are cut, leaving low stumps the width of a palm (10-15 cm). If the soil is moist, then the tubers are left to dry for a couple of hours, and then the ground is very carefully cleaned off. Damaged tubers are immediately rejected so that healthy ones do not become infected.
Can you leave dahlias in pots over winter?
Some varieties of dahlias need to be kept in pots. Tuber pots are wrapped in newspaper and packed in a bag. In the spring, the pots are taken out, watered, and then transplanted or divided. In addition, tubers can be stored in sand or sawdust. They need to be checked several times. Rotting areas must be cut out and disinfected, or the affected tubers should be removed. In the spring, a pot of dahlias can be moved to a warm room, and a few tablespoons of water can be added to it to awaken the tubers.
How to Care for Dahlias in Pots
When to plant dahlias in pots? Potted dahlias bloom 40 to 50 days after planting. To get a plant to flower early, dahlia pots can be placed in a warm, well-lit room. Planting can begin at the end of March. After planting dahlias in pots at home, they are placed in a bright, warm place protected from the wind. Insulated loggias or window sills are well suited for these purposes. It is desirable for the flowers to be in the light for about eight hours a day.
Caring for potted dahlias is easy. They do not require weeding, and their roots do not need protection from pests. They can be moved if there is a threat of frost or hurricane, and then put back in their previous place.
Dahlias growing in pots require:
- Treatment from sucking insects
- Loosening of the soil
- Application of fertilizers.
The amount of watering required depends on the air temperature. In cool weather, dahlias should be watered no more than once a week. Meanwhile, in hot weather, the plant may need daily watering.
Read also Growing Daffodils in Ireland?
Frequently Asked Questions (FAQs) about Dahlias in Pots
1. Can I grow dahlias in pots, and if so, what size of pots should I use?
Yes, you can absolutely grow dahlias in pots, and they can thrive beautifully when properly cared for. To ensure healthy growth, choose pots that are at least 12 inches (30 cm) in diameter and depth. This will provide enough space for the dahlia tubers to develop a robust root system. Make sure the pots have good drainage holes to prevent waterlogged soil, as dahlias dislike sitting in water. Additionally, it’s advisable to use a well-draining potting mix enriched with organic matter for optimal results. Regularly check the pot size to ensure it accommodates the growth of the plant and consider moving to a larger container if necessary.
2. What's the best time to plant dahlias in pots?
The ideal time to plant dahlias in pots is in the spring, after the risk of frost has passed and the soil has warmed up. Typically, this falls around late April to early May, depending on your local climate. Planting at this time allows dahlias to establish their root systems and produce vibrant blooms during the summer and fall. If you live in an area with a longer growing season, you can start them indoors a few weeks earlier and then transplant them to pots once the weather is suitable.
3. How often should I water my potted dahlias?
Proper watering is crucial for dahlias in pots. Water them deeply but infrequently, allowing the top inch (2.5 cm) of the soil to dry out between watering sessions. The frequency will depend on your climate and the pot’s size, but as a general rule, you might need to water every 2-3 days during hot, dry spells and less frequently during cooler periods. Be sure to water at the base of the plant to avoid wetting the foliage, as damp foliage can lead to diseases. Always adjust your watering schedule based on the specific needs of your dahlia and the prevailing weather conditions.
4. Can I order Netherlands dahlia tubers or potted dahlias from your online store?
Yes, you can order dahlia bulbs from our online store. We typically offer a variety of dahlia bulbs for purchase during the fall. Ordering in the fall allows you to receive your bulbs in time for spring planting, ensuring they have the best chance of thriving in your garden.
5. Do potted dahlias require fertilizer, and if so, how often should I fertilize them?
Yes, potted dahlias benefit from regular fertilization to encourage healthy growth and abundant blooms. Use a balanced, water-soluble fertilizer with a ratio of 10-10-10 or similar. Begin fertilizing when your dahlias start producing leaves, and continue every 2-4 weeks throughout the growing season. Follow the manufacturer’s instructions for the recommended dosage, as over-fertilizing can harm your plants. Additionally, consider using a slow-release fertilizer at the beginning of the growing season for a steady supply of nutrients. Always water your dahlias after fertilizing to distribute the nutrients evenly in the soil.