House & Garden Magnesium Boost

House & Garden Magnesium Boost is a concentrated magnesium and nitrogen supplement formulated to support longer vegetative growth phases and larger-leafed plant varieties. Magnesium and nitrogen are structural components of chlorophyll — the pigment that drives photosynthesis — making this additive a targeted correction for gardens that need more from their base nutrient program.

House & Garden Magnesium Boost Specifications

Key product details for House & Garden Magnesium Boost, SKU HGMBO01L.

Why Choose House & Garden Magnesium Boost

Magnesium deficiency is one of the most common mid-cycle problems in hydroponic and soil gardens. Symptoms — yellowing between leaf veins, slowing vegetative growth, reduced canopy density — can appear even when base nutrients are dosed correctly, particularly with large-leafed strains or in soft-water systems where magnesium is naturally low. Magnesium Boost is designed to fill that specific gap without requiring a full nutrient program swap.

• Targeted mineral supplementation: Supplies both magnesium and nitrogen, the two elements that form the core structure of chlorophyll molecules. Adding this where deficiency is present restores the plant’s capacity for photosynthesis rather than masking symptoms.
• Compatible with extended vegetative phases: Formulated specifically to support longer vegetative growth, making it relevant for growers running extended veg windows or working with varieties that build large, dense canopies before transitioning.
• From a well-established nutrient brand: House & Garden has a long record in the Dutch-style nutrient space. Their products are designed to work within a complete feed program, and Magnesium Boost fits that integrated approach — use it alongside their base nutrients when plant response signals a need for extra magnesium.
• Concentrated liquid format: A 1-liter bottle goes a long way when used as a targeted additive at supplemental dose rates. Liquid concentrates mix readily into reservoir water and distribute evenly through drip or flood-and-drain systems.

Best Uses for House & Garden Magnesium Boost

This additive is most useful as a corrective or preventive supplement rather than a primary nutrient source. The following are the situations where growers typically reach for it:

• Large-leafed or fast-growing varieties: Plants with wide leaf surfaces have higher chlorophyll demands and can deplete available magnesium faster than smaller varieties. Magnesium Boost provides the additional supply these genetics need during peak vegetative growth.
• Soft-water or RO-water systems: Reverse osmosis and soft-water sources strip out naturally occurring calcium and magnesium. Growers running RO water as their base often find that standard base nutrients alone do not fully replace what was removed. Magnesium Boost supplements the magnesium side of that equation.
• Extended vegetative growth cycles: The longer a plant stays in veg, the more total magnesium it consumes through leaf production and root development. Adding Magnesium Boost during a long veg phase helps maintain consistent chlorophyll density and canopy color.
• Correcting interveinal chlorosis mid-cycle: Yellowing between leaf veins while main veins stay green is a hallmark sign of magnesium deficiency. Magnesium Boost can be added to the reservoir or applied as a foliar spray to address the deficiency without disrupting the rest of the feed schedule.
• Hydroponics, coco coir, and soil: The liquid concentrate is compatible with recirculating hydroponic systems, run-to-waste drip systems, coco substrates, and container soil grows. Use it in any system where the base nutrient program is not supplying sufficient magnesium.

If you are building out a comprehensive additive stack, pairing Magnesium Boost with a quality root enhancer like Advanced Nutrients Tarantula supports both canopy development and root zone health throughout the vegetative phase. For growers looking to round out their organic amendment program, Earth Juice Hi-Brix Molasses works well alongside mineral supplements in soil and amended media.

Dosing Guidelines

House & Garden does not publish specific dose rates for Magnesium Boost in the canonical product data available for this listing. The following general guidance applies to liquid magnesium supplements of this type and should be verified against the current House & Garden feed chart before use:

• Start with a low supplemental dose — typically 0.5–1 ml per liter (roughly 2–4 ml per gallon) — and increase only if deficiency symptoms persist after one to two watering cycles.
• Always add supplements to reservoir water after the base nutrients are fully dissolved. Check EC before and after adding Magnesium Boost to understand the contribution to total dissolved solids.
• If applying as a foliar spray to address acute deficiency, use a diluted solution and spray during the lights-off period or early in the light cycle to avoid leaf burn.
• Use the House & Garden nutrient calculator available on their website to integrate Magnesium Boost into your complete feed schedule across growth stages.

Consult the label and the manufacturer’s current feed charts for confirmed dose rates before adding Magnesium Boost to your program.

Sources & Further Reading