Ultimate General Hydroponics Autoflower Feeding Schedule Guide

Growing autoflowers in a hydroponic system? Getting the feeding schedule right is crucial. This guide breaks down the exact General Hydroponics nutrient plan for every growth stage—from seedling to harvest—so you can maximize yield, avoid deficiencies, and grow healthy, potent plants with confidence.

So, you’ve decided to grow autoflowering cannabis using a hydroponic system—smart move. Autoflowers are fast, resilient, and perfect for indoor setups, especially when you’re using a high-quality nutrient line like General Hydroponics (GH). But here’s the catch: their rapid life cycle means you can’t afford to mess up the feeding schedule. One wrong move, and you could stunt growth, burn roots, or end up with a weak harvest.

That’s where this guide comes in. We’re diving deep into the **General Hydroponics autoflower feeding schedule**—a step-by-step plan tailored specifically for hydroponic growers. Whether you’re using a DWC (Deep Water Culture), NFT (Nutrient Film Technique), or drip system, this schedule will help you deliver the right nutrients at the right time. No guesswork. No stress. Just healthy, vigorous plants from seed to harvest.

Autoflowers don’t follow the same rules as photoperiod plants. They switch from vegetative growth to flowering based on age—usually around 3–4 weeks after germination—regardless of light schedule. This means your feeding strategy must be precise and timely. With General Hydroponics’ trusted 3-part system (FloraGro, FloraMicro, and FloraBloom), you have everything you need to support your plant through every phase. But knowing *when* and *how much* to feed is the real secret.

Key Takeaways

• Autoflowers have a fixed life cycle: They transition from veg to flower automatically based on age, not light cycles, so timing your feed is everything.
• Start light with nutrients: Young autoflowers are sensitive—begin with 25–50% strength of the recommended dose to avoid nutrient burn.
• Use a 3-part base nutrient system: General Hydroponics FloraGro, FloraMicro, and FloraBloom form the core of a balanced feeding schedule.
• Adjust EC and pH daily: Monitor electrical conductivity (EC) and pH levels to ensure optimal nutrient uptake in hydroponic systems.
• Supplements boost performance: Additives like Cal-Mag, Silica, and bloom boosters can enhance growth when used at the right time.
• Flush before harvest: Stop nutrients 7–10 days before harvest to improve flavor and smoothness of your final product.
• Track everything: Keep a grow journal to refine your feeding schedule for future grows.

Quick Answers to Common Questions

Can I use General Hydroponics nutrients for autoflowers?

Yes! GH’s 3-part system is ideal for autoflowers. Just adjust the ratios and start with lower doses to avoid nutrient burn.

When should I start feeding my autoflower?

Wait until week 2. Use mild nutrients at 25% strength. Seedlings don’t need food right away.

How often should I change the nutrient solution?

In hydroponics, change the solution every 5–7 days. Top off with pH-balanced water between changes.

What pH should I use for autoflowers in hydro?

Keep pH between 5.5 and 6.0. This range ensures optimal nutrient uptake in hydroponic systems.

Do I need to flush my autoflower before harvest?

Yes. Flush with plain water for 7–10 days before harvest to remove excess nutrients and improve flavor.

Understanding Autoflower Growth Stages

Before we jump into the feeding schedule, let’s quickly break down the lifecycle of an autoflower. Knowing what your plant is doing at each stage helps you understand *why* certain nutrients are needed.

Seedling Stage (Week 1–2)

This is the most delicate phase. Your autoflower has just sprouted and is developing its first true leaves. Roots are tiny and sensitive. At this point, the plant is still relying on stored energy from the seed, so it doesn’t need much—if any—nutrients.

Overfeeding here is a common mistake. Even mild nutrient solutions can overwhelm young roots and cause burn. Stick to plain, pH-balanced water (pH 5.5–6.0) for the first few days. If you must feed, use a mild seedling formula or 25% strength of General Hydroponics’ base nutrients.

Vegetative Stage (Week 3–5)

Now your plant is growing fast. Leaves multiply, stems thicken, and roots expand into the hydroponic medium. This is when nitrogen (N) becomes critical—it fuels leaf and stem development.

During veg, your autoflower will benefit from a higher ratio of FloraGro and FloraMicro. Think of it as the “growth engine” phase. But remember: autoflowers have a short veg window. You only have about 2–3 weeks of true vegetative growth before they start flowering. That means every feed counts.

Flowering Stage (Week 6–10+)

Here’s where things shift. Your plant begins forming buds, and its nutrient needs change dramatically. Nitrogen demand drops, while phosphorus (P) and potassium (K) skyrocket. These elements support flower development, resin production, and overall yield.

This is when FloraBloom takes center stage. You’ll gradually increase its ratio while reducing FloraGro. The transition should be smooth—don’t shock the plant with sudden changes.

Late Flowering & Ripening (Week 9–12)

In the final weeks, your plant focuses on ripening buds. Nutrient uptake slows, and excess salts can build up in the system. This is the time to begin flushing—stopping nutrient input and feeding only pH-balanced water.

Flushing removes residual nutrients from the plant, resulting in a cleaner, smoother smoke. Most growers flush for 7–10 days before harvest.

General Hydroponics 3-Part Nutrient System Explained

General Hydroponics’ Flora Series is the gold standard for hydroponic growers—and for good reason. The three-part system (FloraGro, FloraMicro, and FloraBloom) gives you complete control over your plant’s nutrition. Let’s break down what each does.

FloraMicro: The Foundation

FloraMicro provides essential micronutrients like calcium, magnesium, iron, zinc, and copper. It’s used in every feeding, regardless of growth stage. Think of it as the “vitamin” part of the diet—small but vital.

Always add FloraMicro first when mixing nutrients. It stabilizes the solution and prevents nutrient lockout.

FloraGro: The Growth Booster

High in nitrogen and secondary nutrients, FloraGro promotes strong vegetative growth. It’s your go-to during the early and mid-vegetative stages. Use it more heavily when your plant is leafing out and developing structure.

But don’t overdo it in flower—too much nitrogen can lead to stretched, leafy buds with lower potency.

FloraBloom: The Flower Fuel

Packed with phosphorus and potassium, FloraBloom is essential for bud development. As your autoflower enters flowering, increase the ratio of FloraBloom while tapering off FloraGro.

This shift signals the plant to stop focusing on leaves and start putting energy into flowers. The result? Dense, resinous buds with maximum yield.

Week-by-Week Feeding Schedule

Now for the main event: your **General Hydroponics autoflower feeding schedule**. This plan assumes a standard 10–12 week lifecycle and uses a hydroponic system with daily nutrient changes (or every 2–3 days in recirculating setups). Always start with low doses and increase gradually.

Week 1: Germination & Seedling

Keep it simple. Use only pH-balanced water (5.5–6.0). No nutrients yet. Your seedling is still using stored energy. If you’re using rockwool or coco, pre-soak in pH-adjusted water.

Tip: Use a humidity dome to maintain moisture. Light should be low intensity (18–24 hours on).

Week 2: Early Seedling

First true leaves appear. You can now introduce a mild nutrient solution:
– FloraMicro: 0.5 mL/L
– FloraGro: 0.5 mL/L
– FloraBloom: 0.25 mL/L
Total EC: 0.4–0.6
pH: 5.5–6.0

This is about 25% strength. Monitor for signs of stress—yellowing or curling leaves mean you’ve gone too strong.

Week 3: Early Vegetative

Growth picks up. Increase nutrients slightly:
– FloraMicro: 0.75 mL/L
– FloraGro: 1.0 mL/L
– FloraBloom: 0.5 mL/L
Total EC: 0.6–0.8
pH: 5.5–6.0

Add a Cal-Mag supplement if you notice weak stems or leaf curl. Autoflowers can be prone to calcium deficiency in hydro systems.

Week 4: Mid-Vegetative

Your plant is now in full veg mode. Boost nitrogen:
– FloraMicro: 1.0 mL/L
– FloraGro: 1.5 mL/L
– FloraBloom: 0.75 mL/L
Total EC: 0.8–1.0
pH: 5.5–6.0

Consider adding a silica supplement (like GH MaxiGro Silica) to strengthen cell walls and improve stress resistance.

Week 5: Late Vegetative / Pre-Flower

Some autoflowers begin showing pre-flowers this week. Start transitioning:
– FloraMicro: 1.0 mL/L
– FloraGro: 1.0 mL/L
– FloraBloom: 1.0 mL/L
Total EC: 1.0–1.2
pH: 5.5–6.0

The 1:1:1 ratio prepares the plant for flowering. Watch for pistils (white hairs) at node sites.

Week 6: Early Flowering

Flowering begins. Shift to bloom dominance:
– FloraMicro: 1.0 mL/L
– FloraGro: 0.5 mL/L
– FloraBloom: 1.5 mL/L
Total EC: 1.2–1.4
pH: 5.5–6.0

Introduce a bloom booster (like GH Floralicious Plus) to enhance terpene and resin production.

Week 7–8: Mid-Flowering

Buds swell rapidly. Maximize PK:
– FloraMicro: 1.0 mL/L
– FloraGro: 0.25 mL/L
– FloraBloom: 2.0 mL/L
Total EC: 1.4–1.6
pH: 5.5–6.0

Reduce FloraGro to avoid nitrogen toxicity. Watch for dark green leaves—this could mean too much nitrogen.

Week 9–10: Late Flowering

Buds ripen. Begin reducing nutrients:
– FloraMicro: 0.75 mL/L
– FloraGro: 0 mL/L
– FloraBloom: 1.5 mL/L
Total EC: 1.2–1.4
pH: 5.5–6.0

Start flushing with plain water 7–10 days before harvest. This removes excess salts and improves flavor.

Week 11–12: Harvest Prep

Feed only pH-balanced water. EC should drop to 0.4–0.6. Monitor trichomes with a magnifying glass—harvest when 70–90% are cloudy or amber.

Monitoring & Adjusting Your Feed

Even the best schedule needs fine-tuning. Every grow is different. Here’s how to stay on track.

Check pH and EC Daily

In hydroponics, pH affects nutrient availability. Keep it between 5.5 and 6.0 for most of the grow. Use a reliable pH meter and adjust with GH pH Up or Down.

EC (electrical conductivity) measures nutrient strength. Use a TDS or EC meter to ensure you’re not under- or over-feeding. Autoflowers prefer lower EC than photoperiod plants—usually between 0.4 and 1.6.

Watch for Deficiencies and Toxicities

Yellowing lower leaves? Could be nitrogen deficiency—or overwatering. Purple stems? Might be phosphorus deficiency. Brown leaf tips? Likely nutrient burn from high EC.

Take photos and compare them to deficiency charts. Adjust your feed accordingly.

Keep a Grow Journal

Track everything: nutrient doses, pH, EC, plant height, leaf color, and observations. This helps you replicate success and fix problems faster next time.

Supplements & Additives to Enhance Growth

While the 3-part system is powerful, supplements can give your autoflowers an edge.

Cal-Mag

Prevents calcium and magnesium deficiencies. Use weekly during veg and early flower, especially in soft water areas.

Silica

Strengthens stems and improves resilience to heat and pests. Add 1–2 mL/L during veg and early flower.

Bloom Boosters

Products like GH Floralicious Plus or Diamond Nectar enhance terpene production and bud density. Use from week 6 onward.

Enzymes

Break down dead root matter and improve oxygen uptake. Use weekly in hydro systems to keep roots healthy.

Common Mistakes to Avoid

Even experienced growers slip up. Here’s what to watch for:

• Overfeeding early: Young roots can’t handle strong nutrients. Start low and slow.
• Ignoring pH: Nutrients won’t absorb if pH is off. Check it every time you feed.
• Skipping the flush: Residual nutrients can make smoke harsh. Always flush before harvest.
• Using too many additives: More isn’t better. Stick to 2–3 supplements max to avoid interactions.
• Not adjusting for strain: Some autoflowers are heavier feeders than others. Observe and adapt.

Conclusion

Growing autoflowers with General Hydroponics in a hydroponic system is one of the most rewarding ways to cultivate cannabis indoors. With their fast turnaround and high resilience, autoflowers are perfect for both beginners and seasoned growers. But success hinges on one thing: a precise, well-timed feeding schedule.

By following this **General Hydroponics autoflower feeding schedule**, you’re giving your plants the exact nutrition they need—when they need it. From the delicate seedling stage to the final flush, every step is designed to maximize health, yield, and potency. Remember to monitor pH and EC, use supplements wisely, and keep detailed notes. Your next grow will be even better.

So grab your Flora Series bottles, set up your system, and get growing. With the right plan, you’ll be harvesting top-shelf buds in just 10–12 weeks.

Frequently Asked Questions

What is the best General Hydroponics feeding schedule for autoflowers?

The best schedule starts with mild nutrients in week 2, increases during veg, shifts to bloom dominance in week 6, and ends with a flush before harvest. Always monitor pH and EC.

Can I use GH nutrients in soil?

Yes, but this guide is for hydroponic systems. In soil, nutrient release is slower, so feeding schedules differ.

Why are my autoflower leaves turning yellow?

Yellow leaves can signal overfeeding, nitrogen deficiency, or pH issues. Check your EC, pH, and nutrient ratios.

How much light do autoflowers need?

Autoflowers thrive under 18–24 hours of light per day. LED or HPS lights work well in hydroponic setups.

Can I reuse nutrient solution?

It’s not recommended. Old solution can harbor pathogens and have imbalanced nutrients. Always use fresh mix.

What’s the ideal EC for autoflowers?

Start at 0.4–0.6 in seedling stage, increase to 1.0–1.4 in flower, and drop to 0.4–0.6 during flush.