Lupins in the garden: sowing, flowering and care from A-Z

Once a typical classic on farms, their rural charm makes lupins a popular perennial in urban areas, too, where they add a summery touch with lots of colour. Since it is relatively frugal in terms of care, it also takes up very little time for itself. In the following guide you can find out everything about it, as well as about propagation, hibernation and much more.

Location

Your demands on the location, which decides how strong, lush and floriferous lupins thrive. In order to create optimal conditions, the location should meet the following criteria:

• Light conditions: sunny to semi-shady
• Around four hours of sunlight a day is ideal
• Wind-protected but airy location
• loves warmth
• Gets along very well with plant neighbors
• As a soil conditioner, plant neighbors enjoy their presence
• She feels just as comfortable in the perennial bed as she does cultivated in a bucket

soil condition

Lupins have the property of improving soil conditions. Its long roots loosen up even compacted soil. Nevertheless, she herself likes the following soils:

• Loose, deep soil
• Mixing sand into heavy soil makes them grow denser
• Soil that is permeable to water and does not become waterlogged
• low in calcium
• moderately nutritious
• pH: between 5.0 and 6.0

substrate

If the lupine is planted in a bucket, make sure that a high-quality substrate is used instead of cheap, conventional potting soil. This usually compacts very quickly and the risk of waterlogging and mold growth is high. A substrate that is particularly water-permeable is ideal. Perlite loosens the substrate. Coconut fibers ensure good water storage without provoking waterlogging. A low sand content can be included as an alternative to coconut fibers. Otherwise, the substrate should have the same properties as described above for garden soil.

Best planting time

Flower perennials generally have the best planting time in early autumn. This gives them enough time to get used to their new environment and, above all, to establish their roots. The planting time in autumn promotes the formation of flowers in the following year. It is necessary to ensure that after planting the first frost is not yet expected.

Preferred Lupinus

If lupins are preferred, they can still be planted in spring. Mid-May is a good time. The ice saints are to be awaited so that the plants are not exposed to frost after they have spent the winter in a warmer environment.

Plant

garden bed

• Soak the root ball in a bucket of water for about 10 minutes to help loosen it from the pot
• Dig a planting hole twice the size of the root ball
• Ideally, lay out a two-centimetre-thick drainage layer of quartz sand or gravel on the floor
• Place the plant in the middle of the planting hole and close the hole with the excavated earth
• Slightly press the soil firmly onto the surface
• Water moderately
• Planting distance: between 30 centimeters and 50 centimeters

bucket

When cultivating in a bucket, proceed as described under "Garden bed". You should use a bucket that is large enough so that there is a distance of at least eight to ten centimeters between the lateral root ball and the bucket walls. Above all, an appropriate depth must be given so that the roots can develop well and the perennial can grow optimally.

The substrate surface should have a distance of at least two centimeters to the edge of the bucket so that any sludge does not spill over after watering. A drainage hole in the bottom of the bucket allows excess water to drain away and prevents waterlogging.

Pour

Planted in the garden soil, adult lupins usually do not need watering. They are deep-rooting and draw moisture from the depths of the soil. Watering is only done when there are long periods of drought. Young plants in the first year of life and specimens cultivated in tubs must be watered occasionally. When they are young, they do not yet have the deep root system. In buckets, a lupinus does not have the opportunity to obtain its own water from the ground. Water before the soil/substrate dries out on the surface. Here the thumb test helps to find the optimal time:

• Press thumb into soil/substrate surface
• If it can be pressed in less than two centimetres: watering required
• If it can be pressed in more than two centimetres: no watering required

Fertilize

Lupins like soil that is not very nutritious and they do not tolerate large amounts of lime. They produce nitrogen themselves through small nodules that grow on their roots. Therefore, fertilizing is not absolutely necessary. If you still want to fertilize, you should limit yourself to mature compost. This can be administered at the beginning of the official gardening season in May. Fertilization should be avoided in autumn, as the wolf bean has to prepare for the winter and slowly goes into dormant mode. Fertilizer would interfere with that. In principle, young plants should not be fertilized in the first year of life.

Cut

In principle, cutting is not necessary for lupins. Nevertheless, it can be useful and support the perennial especially in the formation of flowers and promote dense growth. The following procedure/cutting methods are recommended:

• Cut off the panicles after flowering - this increases the chance of a second flowering in late summer/early autumn
• If propagation by self-sowing is not desired, the panicles must be cut off after flowering
• In autumn, cutting back to a height of ten centimeters promotes dense growth in the following year
• Pruning can also be done in spring, but could result in delayed flowering

hibernate

Depending on the variety, Lupinus show a winter hardiness of up to minus 25 degrees Celsius, provided they are planted in garden soil. As deep-rooting, the roots reach a depth of about 1.50 meters. There they are well protected from the freezing cold and therefore do not need winter protection. This is different for specimens in tubs. Due to the thin bucket walls and floors, the cold reaches the roots almost "unchecked". Symptoms of frostbite are then not uncommon. With the following measures you can create protection against the cold so that you can survive the coldest winter without any problems:

• Place an insulating base such as styrofoam, wood or cardboard under the bucket
• Cover the substrate surface thickly with straw, leaves or pine needles
• Wrap bucket walls several times with fleece or foil

multiply

Although the lupine can reproduce independently through seeds, many hobby gardeners prefer it the controlled propagation - especially since you can also determine the color of new plants in this way can. Propagation can be carried out in various ways and requires no special skills or knowledge.

sowing

You have the option of obtaining seeds from a lupine or buying them from specialist retailers. With the seed from a lupine you do not influence the color of the flower. When buying seeds, you have all sorts of colors to choose from. The seed of a lupinus is ripe when the pods are completely dry and greyish-brown in colour. You can choose between different sowing methods.

Instructions for bed sowing

• Best time for sowing: between May and August
• Best location: sunny and warm (no direct sun)
• Dig the soil deeply and loosen it up well
• Remove weeds, old root remains, stones and anything else that doesn't belong in the ground
• Enrich the soil with compost and horn shavings and mix well
• Distribute seeds on the soil and cover about one to two centimeters with soil
• Seed spacing: about 30 centimeters
• Spray the soil liberally with water (do not use a watering can as the seeds may float away)
• Stretch transparent film over the seeds (increases the chance of germination)
• Open foil every two days to aerate and moisten the soil (daily on hot days)
• Germination usually takes place after a few days
• Remove the foil from the first growth of leaves and allow the soil to dry slightly before watering in the future

Instructions for sowing indoors/greenhouse

Sowing in greenhouses or in the home is basically the same as sowing in the garden bed. Only the following different factors should be considered:

• Best time for sowing: all year round
• Soak seeds in water between 12 and 24 hours before sowing
• Use potting soil or a peat-sand mixture
• Soaked seed is pressed about one to two centimeters into the substrate/soil
• Location: bright, warm window seat without direct sunlight
• Avoid dry heating air
• Prick out when the first leaves appear

cuttings

• Best time: spring
• Choose suitable cuttings from the middle of the stem
• Length of suitable shoots: between 10 and 15 centimeters
• Cuttings should have four to six leaves
• Separation from the mother plant takes place about 0.5 centimeters below an eye
• Halve the lower leaves with a sharp knife
• Remove any buds and flowers
• Put the cutting halfway into a flower pot with potting soil or a nutrient-poor substrate
• Water well and continuously keep the soil moist without overwatering
• Location: in a bright window
• Optimum ambient temperature: 20 degrees Celsius to 25 degrees Celsius

Diseases

Lupins are very robust against diseases. It is usually due to care mistakes such as too much irrigation water or fertilizer. If the perennial is permanently too wet, root rot can quickly form. Since these are deep in the ground, digging them out without damaging the roots is almost impossible. Here you can only hope that a longer water break will allow for a recovery.

If there is an oversupply of fertilizer, this is usually reflected in a yellow discoloration, decreasing stability and premature wilting of the flowers. Further fertilization should be avoided in any case and you can only hope that the perennial will recover.

Leaf shedding disease (Stemphylium spp.)

This is a fungal infection that causes lupins to become ill at temperatures above 15 degrees Celsius and high humidity for more than twelve hours.

damage picture

• Small, rounded, grey-blue to grey-brown spots on the leaves
• Red-brown spots on stems and pods
• Increased leaf drop
• Rotten vegetation cone
• Plant will die if left untreated

combat

Since leaf thrush can progress rapidly, rapid application of a fungicide is recommended.

pests

The wolf bean is also very resistant to pests. The most common is the lupine aphid.

lupine aphid

Recognize and damage image

• Size: about three millimeters
• Body color: green, brown, transparent, brown-black
• Usually on the undersides of leaves
• In colonies they often gather on the stems
• Sticky coating on leaves (honeydew)
• Yellow spots form at the puncture sites where they drew out plant sap
• growth disorders
• Buds don't open

combat

With a minimal infestation, it is often sufficient to get the lupine aphid off the perennial with a powerful jet of water. Otherwise, a strong soapy solution has proven to be excellent against the pests:

• Soft soap is best suited for the lye
• Pour plenty of it into clear water and mix well
• The lye should be relatively highly concentrated (water cloudy due to the soap)
• Pour soapy water into a spray container
• Spray the lupine generously on the underside of the leaves as well
• If necessary, repeat the process every other day

Learn more about summer flowers