House & Garden Algen Extract – 5 Liter

House & Garden Algen Extract is a liquid plant additive made from Norwegian Sea Kelp harvested and processed by cold press to preserve the natural compounds in the raw material. The 5-liter bottle is designed for growers who apply the product regularly across multiple feeding cycles and need a larger format that reduces reorder frequency. It belongs to the House & Garden additive lineup and is categorized under growth and bloom boosters.

House & Garden Algen Extract – 5 Liter Specifications

Specification	Value
Brand	House & Garden
Product Name	Algen Extract
Volume	5 Liter
SKU	HGALG05L
Ingredient Source	Norwegian Sea Kelp (cold-press blend)
Product Type	Liquid additive / growth & bloom booster
Category	Nutrients & Additives > Additives > Growth & Bloom Boosters
Shipping Weight	13.6 lb (6.2 kg)

Why Choose House & Garden Algen Extract

Algen Extract occupies a specific role in the House & Garden additive lineup: it provides seaweed-derived compounds to the root zone or foliar surface without the need to formulate from multiple standalone inputs. Here is what sets it apart from generic seaweed products on the market:

• Cold-press extraction: House & Garden produces Algen Extract using a cold-press method rather than heat or chemical hydrolysis. Cold pressing retains more of the naturally occurring compounds in the kelp, which can degrade at elevated temperatures or under harsh chemical processing.
• Norwegian Sea Kelp source: The raw material is Norwegian Sea Kelp, a variety recognized in the industry for its naturally occurring compounds. The geographic origin is stated by the manufacturer and reflected in the product naming.
• Part of an integrated nutrient system: House & Garden designs Algen Extract to work alongside its base nutrient and additive lines. Growers already running House & Garden nutrients can add Algen Extract without compatibility concerns, and the brand publishes a nutrient calculator to help dial in dosing across the full product range.
• 5-liter format reduces handling frequency: At 5 liters, this size is appropriate for commercial or multi-plant operations where smaller bottles would require frequent replenishment. The larger format also reduces per-liter packaging cost compared to the 1-liter or 500 mL sizes.
• Liquid concentrate: The liquid form makes it easy to measure and mix into existing reservoir or foliar-spray routines without dissolution steps required by powdered alternatives.

Best Uses for House & Garden Algen Extract

Algen Extract is a general-purpose seaweed additive suited to both vegetative and flowering stages. Growers typically introduce it as a supplemental feed alongside their base nutrient program. The following uses reflect its product category (growth & bloom booster additive) and the liquid kelp extract format:

• Hydroponic recirculating systems: Add to reservoir alongside base nutrients. The liquid concentrate mixes readily into water and can be dosed with a measuring syringe or dosing pump for precision.
• Coco and soilless media: Apply as part of regular fertigation. Cold-pressed kelp additives are commonly used in coco-based programs to supplement the primary nutrient profile.
• Soil grows: Incorporate into water-in feeds. Kelp-based additives are compatible with organic and conventional soil programs.
• Foliar application: Liquid seaweed extracts can be diluted and applied as a foliar spray during vegetative growth. Follow the manufacturer’s recommended dilution rate for foliar use.
• Commercial multi-strain runs: The 5-liter volume suits commercial cultivators running continuous feeding schedules across multiple tables or reservoirs, where the per-cycle volume justifies the larger bottle size.
• Combination with other House & Garden additives: Algen Extract can be used alongside other products in the House & Garden lineup. Pair it with a root development additive during early veg or with a bloom booster during the flowering stage to support different growth phases.

Compatibility

House & Garden Algen Extract is a liquid additive designed to be compatible with the full House & Garden nutrient system, including their A+B base nutrients for both hydro and soil applications. As a cold-pressed kelp concentrate, it mixes into water-based nutrient solutions without special preparation.

General compatibility considerations for liquid seaweed additives of this type:

• Growing media: Compatible with hydroponic systems (DWC, NFT, ebb-and-flow, drip), coco coir, rockwool, perlite mixes, and organic or amended soil. There is no media-specific restriction inherent to the product format.
• Water pH range: Target reservoir or feed solution pH of 5.5–6.5 for hydroponic use, and 6.0–7.0 for soil, in line with standard House & Garden recommendations for the full additive lineup.
• Other nutrients and additives: Can be combined with conventional base nutrient programs and other seaweed-compatible additives. Growers using products such as organic carbohydrate supplements or microbial inoculants should verify stack compatibility in a test batch before full deployment.
• EC contribution: As an additive at typical dosing rates, Algen Extract contributes a modest EC increment to the overall nutrient solution. Monitor total EC after mixing and adjust base nutrient strength accordingly.

Manufacturer-published specific EC contribution and full compatibility matrix for this product are available through the House & Garden nutrient calculator on their website.

Dosing Guidelines

House & Garden publishes dosing schedules for their full nutrient and additive lineup through their online nutrient calculator. Because exact dose rates per liter or gallon are not reproduced in the product listing data available at time of writing, growers should consult the official feeding chart for Algen Extract.

The following guidelines apply to liquid seaweed additives of this type and are consistent with standard industry practice for concentrated kelp extracts:

• Start at the low end of the manufacturer’s recommended dose range for the first application and observe plant response before increasing.
• Measure using a calibrated syringe or graduated measuring cup. Do not estimate by eye for concentrated additives.
• Add Algen Extract to the reservoir or feed water after measuring and adjusting base nutrient volumes, then mix thoroughly.
• Check EC before and after adding the additive. For recirculating systems, verify the full reservoir EC is within the target range for the current growth stage.
• Adjust dose frequency and concentration across grow and bloom phases per the House & Garden schedule. The manufacturer’s nutrient calculator provides a week-by-week breakdown for both soil and hydroponic programs.

Sources & Further Reading