Roger Burnett - Growing Award-Winning Pelargoniums in a Keder Greenhouse

Roger Burnett, an experienced horticulturalist and specialist in pelargoniums, has spent over fifty years refining the conditions needed to grow strong, uniform, and high-quality plants. When he set out to improve his propagation success and extend his growing season, he chose a Keder Greenhouse - a decision that significantly transformed his production capabilities.

Victorian horticulture popularised the name “geranium” for a variety of tender Pelargonium species, many people still confuse them with the hardy true Geranium plants - even though their hardiness is completely different. 

As you would expect, the tender Pelargoniums need to be treated differently and require a more balanced environment and Roger chooses Keder Greenhouse for the following reasons.

• Stable temperatures to avoid stress and leaf distortion

• Reliable light diffusion to prevent scorching during bright periods

• Good airflow without cold draughts

• Protection from heavy rain and wind, which can damage young stock plants

In traditional glass and polytunnels, Roger found it difficult to maintain this balance.

Seasonal temperature swings, inconsistent light, and structural vibration in high winds all affected plant quality and limited his ability to scale production.

Why Roger Chose a Keder Greenhouse

After reviewing various greenhouse structures, Roger identified several key advantages of the Keder insulated bubble-film cladding system:

1. Superior Insulation - The 9 layer bubble cladding provided outstanding heat retention through winter and cool stability during summer. Roger saw immediate reductions in temperature fluctuations - critical for pelargonium growth.

2. Diffused, Even Light - Keder’s unique film diffuses sunlight naturally. Roger reports fewer incidents of leaf scorch and noticeably more uniform growth across benches, especially in variegated and zonal pelargoniums.

3. Wind Resistance - Living in an exposed rural location, Roger valued Keder’s proven performance in storms. While previous greenhouses suffered panel losses and structural flexing, the Keder structure remained stable - even during winds exceeding 80 mph.

4. Low Running Costs - With less heat loss and efficient natural light, Roger reduced his winter heating bills substantially. This allowed him to overwinter more stock plants comfortably and begin propagation earlier in spring.

   
   

Implementation

In September 2025 the Keder team installed a 6m x 12m Smallholder to add to his existing Keder collection, which was fitted with:

• Full-length staging

• Manual Drop Side Vents

  
  

The structure was erected quickly, and Roger began using it immediately for overwintering pelargonium parent plants and rooting new cuttings.

Roger Burnett - Pelargonium Collection

Results

Improved Plant Quality

Pelargoniums raised in the Keder Greenhouse showed:

• Stronger root systems

• More compact, bushy growth

• Richer leaf colour

• Higher flower production

Roger attributes this to the consistency of the micro-climate inside the structure.

Higher Propagation Success Rate

Cuttings rooted faster and with greater uniformity. Roger increased his propagation success from around 75% to over 90% during the first season.

Extended Growing Season

With reliable insulation and ventilation, Roger is now able to:

• Start propagation earlier (late winter rather than early spring)

• Keep flowering stock going longer into autumn

• Produce sale-ready plants weeks ahead of schedule

  
  

Reduced Heating Costs & Outstanding Insulation Performance

Roger observed energy savings of 30–40%, thanks to the Keder cladding’s insulation. The thermal efficiency also delivered clear advantages during extreme cold spells:

Roger stated “Even though we experienced temperatures as low as -8°C on one or two evenings, I maintained a steady 6°C inside the Keder greenhouse using a single 10kW thermostatically controlled propane gas heater. A similar-sized glasshouse, using two comparable heaters, could only achieve 4°C on the coldest nights. This is real testimony to the insulation properties of the Keder.”

Four-Season Reliability

During severe winter storms, the structure remained completely stable, giving Roger peace of mind and protecting his valuable stock plants.  This level of insulation allowed Roger to protect valuable stock plants with lower energy input, reinforcing the greenhouse’s suitability for professional and specialist growers operating year-round.

Roger stated “The Keder Greenhouse has transformed the way I grow. My pelargoniums have never been healthier. The insulation, the light, the strength in bad weather - it all adds up to a perfect environment. I wouldn’t grow in anything else now.” 

This level of insulation allowed Roger to protect valuable stock plants with lower energy input, reinforcing the greenhouse’s suitability for professional and specialist growers operating year-round.

Conclusion

Roger Burnett’s experience highlights the significant advantages a Keder Greenhouse can bring to specialist growers. For plants that demand stable conditions - like pelargoniums - the combination of insulation, durability, and diffused light results in consistently superior growth and lower operating costs.

Keder Greenhouse continues to support growers like Roger with structures designed for year-round productivity, reliability, and exceptional plant health.